Achievement Guide by stryker115

Version: 1.0 | Updated: 09/23/08 | Printable Version

Tales of Vesperia Achievement Guide

Tales of Vesperia, like most Tales games, is designed to be played 
through multiple times.  You will need a minimum of 2 playthroughs to 
get all Achievements but Low Level Challenger, and another playthrough 
up through the end of Chapter 1 to complete all of them.  Use your 
first playthrough to enjoy the game and pick up what sidequests/events 
you can, as even going for Speedster you can still pick up 
sidequests/events you missed on your first playthrough.

If you want to make sure you don't miss any events, I recommend Kouli's 
excellent event guide at  Following 
this guide carefully will ensure you don't miss any items or titles on 
your first (or second, if you're already playing) playthrough.

For Secret Missions, I would HIGHLY recommend doing them all on your 
first playthrough, as attempting to do them during a Speedster run with 
10x exp may be frustrating and increase the time it takes to get 
through the game. Note that while the achievements unlock immediately, 
there is a title for Yuri that you can only get if you complete them 
all in a SINGLE playthrough.  

For all but the first and last Secret Mission you will get a small 
scene with the word "Great!" appearing to indicate you completed the 
requirement (Secret Mission 12 is an exception, as you will need to see 
the "Great" twice).  If you do not see this scene, you will not get the 
completion upon winning the fight.  Completing the Secret Missions also 
awards you with valuable items.

Special Note about Secret Mission 16:  You MUST get the item to 
complete this during a certain period of time.  Make sure you sleep in 
the inn in Mantaic and get the Mother's Memento BEFORE going to Myorzo 
for the first time.

I've listed the achievements in the order they're shown in the Xbox 
Guide, which isn't the same order they're "numbered" in based on the 
achievement icons.

Normal Achievements

Too Much Free Time (20 points)

Accrue 100 hours of playtime.  You can choose to carry across your 
Records from the Grade Shop on subsequent playthroughs if you don't get 
it on your first.  As soon as the played clock hits 100 hours, the 
achievement will unlock.  If you manage to complete everything else 
quickly or just want this achievement, you can leave the game on and 
time will continue to accrue.

To Points Unknown (10 points)
Fly 100,000 km.  This is a very long distance in the game world, and 
even after doing everything else in the game you will likely have to 
leave the game on with your characters flying across the map 
repeatedly.  This does NOT carry over on an EX New Game.  In my case, 
it took 10 hours of leaving it on while flying around after completing 
almost everything else.

Grand Battles (10 points)

Kill 1,000 enemies in battle.  This one should come naturally during 
your first playthrough, most likely during Chapter 2.

Jackpot (10 points)
Win 100,000 chips in the Nam Combanda Isle gymnasium.  You can randomly 
earn chips in the capsule machines, but poker provides the easiest way 
to earn chips.  The key to winning large amounts of chips is to take 
every double opportunity you're given. Eventually you can get a streak 
of several doubles going, which will reward you with thousands and 
thousands of chips.

Piggybank (10 points)

You will need to have 10,000,000 gald at one time, as this achievement 
is NOT accumulative.  Depending on how patient you are, you can buy 
gels at Nam Combanda Isle and sell them at Yumanju to earn roughly 
175,000 a trip. 

The EX Dungeon has chests with upwards of 150,000 gold in them, so it's 
a good source for money as well.  I recommend getting this on your 
second playthrough, as by that point you'll have multiple Blue Sephiras 
(which stack) and will most likely have learned Happiness 3 on your 
characters (which also stacks).  This strategy coupled with the double 
gald Grade Shop ability make it much easier to reach the total.

If you're still short, keep in mind this achievement does not affect 
anything in the game.  You can get close enough, sell everything you 
own to hit the total and unlock the achievement, and then reload.

They Call Me... (30 points)
Acquire every title for every character.  This is the most difficult 
achievement and you will need to complete both Item Nerd and Monster 
Nerd, as each award a title.  

Character Study (10 points)
Watch every skit.  Your current progress for this is shown in the 
Records screen, and there are roughly 500 skits.  You will see 
indicators for them in the bottom left of the screen, and they appear 
for everything from cooking to story events.

You can unlock all skits in the Grade Shop, and they will be available 
to view at Nam Cobanda Isle.  They will be in a green color indicating 
they haven't been watched yet.  If you don't want to watch each one at 
that point, you can press Start to skip them but still get credit for 
watching them.  Certain skits are very easy to miss, so this will be 
the way most people will end up seeing them all.

No More Grinding (10 points)

Reach the maximum level, 200.  Only one character in your party needs 
to reach level 200 for this achievement to unlock, but most likely all 
characters will be around the same level at that point.  This is 
actually easier than it sounds with the 10x EXP ability from the Grade 
Shop, especially when going through the EX Dungeon.  Each boss will 
give a few hundred thousand experience, meaning a few runs through it 
(which you'll need anyway) will cap your characters.	

Map Nerd (50 points)
Uncover the entire World Map.  This means there can't be ANY gray spots 
still on your map.  It is possible to leave very small areas 
unexplored, making it look like you have discovered everything but not 
unlocking the achievement.  Pulling up the World Map from the menu can 
help illustrate any little gray areas, and if that doesn't work then 
leave this achievement for last.  You may end up finding the missing 
spot just flying around playing the game.  If you want to start a new 
playthrough but haven't completed the map, make sure you carry it 
across using the Grade Shop.

Monster Nerd (30 points)
Complete the Monster Book.  This means that every enemy must be listed, 
and all of them must have their information shown (no ???? entries).  
Use a magic lens on every new monster you encounter, and you will 
gradually work toward this.  Make sure you stock up on Magic Lenses in 
every town you visit.

It is possible to miss this achievement for a playthrough by missing a 
scan on something you only fight once, which includes bosses, certain 
event fights (Capua Nor near the beginning, for instance) and certain 
time sensitive monsters (the knights in Baction, for example).  If a 
fight is split into two parts (like Zagi or Baitojoh), you need to scan 
BOTH.  If you are unsure if you have the scan, use your target button 
to see if the monster shows health information under the name.  If it 
doesn't, you don't have the scan.

Make sure you carry across your Monster Book to your next playthrough 
if there are any you miss.  You will need to clear the EX dungeon and 
the 200 man melee to complete the book, as they enemies you can't fight 
anywhere else.  You will also need to clear the 100 man melee with most 
of your characters, as some of them fight different bosses there.

Item Nerd (30 points)
Complete the Collector's Book.  You aren't actually given the book as 
part of the story - you pick it up in Rita's house after your first 
meeting with her.  Any item you acquire, whether through synthesis, 
purchasing, or finding, ends up in the book.  There are several hundred 
items in total, and many of them are completely missable if certain 
sidequests aren't done.  

Make sure you NEVER sell any weapons, as virtually every weapon can be 
synthesized into other weapons (some several times), and you will need 
a record for all of them to complete the book.  Like the Monster Book, 
the Collector's Book can be carried to another playthrough through the 
Grade Shop.

Little Mad Scientist (10 points)
Synthesize 20 items.  These do not need to be different items, you can 
synthesize an Apple Gel 20 times and get this achievement.  You'll be 
synthesizing so often during gameplay that this should come naturally.

There have been reports that synthesizing more than one item at a time 
(i.e., synthesizing 3 Apple Gels at once) will glitch this achievement.  
If that happens to you, starting another playthrough to get to the 
point where you can synthesize should be fairly quick.  Choosing not to 
carry across "Crafting Skill" in the Grade Shop may reset this total as 

Back Up Plan (10 points)

Activate every save point in the game.  Note that you don't actually 
have to USE them, just "activate" them by stepping on them.  Many save 
points disappear or change as the story progresses, so make sure you 
use each one as you see them.  In particular, Aurnion counts as 3 
different save points at various points, so make sure you get them all.  
Note that this must be done in a single playthrough, consecutive 
playthroughs reset which save points you've used.

Vesperia master (0 points)

Earn every other achievement in the game.

The Hit that Keeps On Hitting (20 points)	

Achieve a 100 hit combo.  This becomes fairly easy once you get Mystic 
Artes and Super Chain abilities, as Yuri can chain Shining Dragon + 
Brutal Fang + chained artes + BA + MA for a LOT of hits on his own.  If 
you don't get this during the game, you can use the "Rita Grade 
Farming" technique.

Secret Achievements
Eureka! (10 points)

Synthesize a single item.  Like Little Mad Scientist, there seems to be 
a glitch that will cause you to miss this achievement if you synthesize 
more than one item at a time.

First Strike (20 points)

Execute your first Fatal Strike.  You earn this ability during Chapter 
1, although at first it will be difficult to do in non-boss encounters 
as you will most likely kill monsters before they become strike-able.  
To execute a fatal strike, one of the three bars (shown under the 
monster's name when targeting it) must be depleted, then it must be hit 
with an arte of that color. You can deplete the bars using normal 
attacks of the corresponding direction or artes of the corresponding 
color.  You can check in the Artes screen to determine what artes 
correspond to what colors.  

Yuri using Brutal Fang will quickly cause a Fatal Strike indicator to 
appear, and many of Rita's advanced spells hit enemies multiple times.  
Note that the fatal strike bar does not take damage into effect at all, 
so using Minimum Damage skills will allow you to execute fatal strikes 
very easily without killing the enemy.  

Big Game Greenhorn (20 points)

Kill a Giganto Monster.  You will most likely run into your first, 
Hermit Drill, in the Weasand of Cados.

Big Game Hunter (50 points)

Kill all 9 Giganto Monsters.  More than likely you will need to come 
back to certain areas later to kill them, as some of them (like Brutal 
and Brucis) may be way above your level when you first see them.

In order of level the monsters are:

Hermit Drill - Weasand of Cados, first area along the lower path.

Medusa Butterfly - Sands of Kogorh, on the left side after passing    
through the oasis.

Pterobronc - Mt. Temza, crater near the entrance, will appear only 
after acquiring Ba'ul.  You will also fight him as part of the Guild 
Quest events.

Chimera Butterfly - Quoi Woods, enter from the northern side and burn 
the bush a little way in on the right.  You will need the level 4 or 
higher Sorcerer's Ring.

Poseidon - Enduring Shrine of Zaude, right after fighting Yeager.

Fenrir - Erealuman Crystalands, take the long side path to the right of 
the path leading down to the aer krene where you fight the boss.

Brutal - Overworld, appears north of Deidon Hold.  You see him the 
first time after passing through the Blade Drifts, but will most likely 
want to fight him after your party has reunited.

Griffin - Overworld, east of Yumanju.  If he's not up, try sleeping in 
an inn and coming back.

Brucis - Egothor Forest, along a winding path to the south of the save 
point before going into the cave.  You will probably want to come back 
to fight him later, as he may be 10 or more levels above you when you 
are there for the story.

Smarty-pants (10 points)
Answer the Tales Trivia questions correctly at Nam Cobanda Isle.  Start 
this event by talking to the Kowz standing behind a desk across from 
the poker table in the gymnasium.  He will ask you to gather five 
books, located in:

Heliord, Chevalier's HQ in the back room
Mantaic, Inn along the back wall
Aurnion, HQ on the dresser on the left
Halure, Mayor's House on the dresser on the left
Capua Torim, Fortune's Market HQ, bookcase behind the guard on right

After returning to him, he will ask the Tales Trivia questions as part 
of Karol's test.  The answers are:

September 30, 1998
Raine Sage
Presea Combatir,
Ishtar turned to stone

Speedster (15 points)

Complete the game in under 15 hours.  This is most likely impossible on 
the first playthrough, but fairly easy with Grade Shop perks.  Make 
sure you get 10x Experience, carry across all of your items, can carry 
99 Holy Bottles and set the game to Easy.  Avoid all non-boss 
encounters when possible (using the Holy Bottles) and hold X+A to 
quickly skip through dialogue.  You will more than likely finish in 
around 10 hours if you don't do any sidequests you missed.

Ahhh, Memories (30 points)
Clear the EX Dungeon.  This dungeon is not automatically unlocked after 
beating the game.  To enter it, you must take the following steps:

BEFORE completing the events at Zaude, fly to Pharoeh's Crag and enter 
the portal there.  Talk to the sage in the farthest back house, and 
choose to rest there when asked.

After completing the game, load your clear file and go back to Yormgen 
through the portal at Pharoeh's Crag.  Talk to the sage again, and he 
will give you a book.  Fly to Dahngrest to see a scene about an 
earthquake, then fly over the Yurzorea continent (where there used to 
be mountains) to see a scene as you pass over the entrance.  You can 
then land near the portal and enter the dungeon.

The dungeon has multiple paths and many monsters you will need to 
catalog if you are working on Monster Nerd.  At certain points of the 
dungeon, you will be able to exit completely, but you will have to 
enter at the same point every time with everything reset.  To complete 
it, you must acquire 15 or more Fake Gald and use that to go through 
the black portal after fighting either Duke Memory or Alexei Memory.  
You will then face the final boss of the EX Dungeon.  

Fake Gald is awarded randomly after killing bosses or found in chests, 
and you will be given one the first time you enter the dungeon.  Note 
that to open the treasure chests in each area, you must kill enemies in 
that room first.  As it is random, it may require several runs through 
here to get enough to complete it.  I recommend going through the EX 
Dungeon on a playthrough with 10x EXP, so you can go for the max level 
achievement as well.  Completing this dungeon is one of the 
requirements for unlocking the 200 Man Melee at Nordopolica.

Recovered the Aque Blastia (100 points)

Earned at the end of Chapter 1, after defeating Barbos.

Ended Alexei's Ambitions (150 points)

Earned at the end of Chapter 2, after defeating Alexei.

Defeated the Adephagos (200 points)

Earned at the end of Chapter 3, after defeating Duke's second form.  
The achievement will unlock after the credits are complete.

Bunny Guild Member (10 points)

Acquire all bunny guild attachments and wear them for 5 hours.  You get 
these accessories from the Bunny Guild Leader, the old man standing in 
the back left corner of the Union HQ entry in Dahngrest.  He will award 
you with different attachments as you obtain titles, with all of them 
being available with roughly 80% of all titles earned.  You will know 
when you have earned them all when you get the Black Bunny Ears 
attachment for Yuri.

You will need to equip the bunny ear attachments on Yuri, Judith, 
Estelle and Rita and then continue playing for 5 hours.  Note that 
anything that switches your party (like the Coliseum battles or story 
events) will reset this timer, so it is best to leave this until near 
the end.  The achievement will pop after 5 hours of having them 
equipped without your party changing.

Low Level Challenger (10 points)

Complete Chapter 1 by defeating Barbos with everyone in your party 
under level 15.  This is impossible without the 1/2 EXP ability from 
the Grade Shop.  Like Speedster, avoid all random encounters using Holy 
Bottles and you will most likely beat him around level 12.

Secret Mission 1 (5 points)

Defeat Zagi without letting Estelle take serious damage.  If you hit 
him often enough, he will most likely focus completely on you and 
ignore her as she heals you.

Secret Mission 2 (5 points)

Attack Goliath's heel as he charges up his super attack.  You will need 
to use Free Run to get behind him, then hit him in the heel when you 
see him charging the attack.  It will take a couple hits to knock him 
over, so using an arte that hits multiple times will help.

Secret Mission 3 (5 points)

Stun Gattuso using the plants.  Note that you will NOT get the scene if 
you stun him at the same time you stun yourself or another party 
member.  The easiest way to get this is to wait until he gets close to 
a plant, then hit the plant with Azure Edge so you will not be caught 
in the stun powder.

Secret Mission 4 (5 points)

Knock Zagi over the side of the boat.  One of the more difficult Secret 
Missions, as you may accidentally kill him before completing it.  Note 
that the battle area is a circle and you will need to be as close to 
the walls of the boat as possible.  Then, you can either wait until he 
attacks you with Light Spear and use Overlimit while he's above you 
(which should knock him over), or get him close to the edge, knock him 
off the ground yourself using an arte, then active Overlimit while he's 
in the air to send him over.  I found Crushing Fang (the arte where 
Yuri uppercuts the enemy) worked the best for getting him off the 

Secret Mission 5 (5 points)

Knock the Dread Giant over by attacking its rear legs while it's 
standing on them.  It only stays on them for a brief period while 
pounding its chest, after which it falls to the ground again.  Like 
Secret Mission 2, it's best to use an arte/attack that hits multiple 
times as soon as you see it rear back.  You will probably have more 
luck using Free Run to get around behind him rather than running in 
under him when he stands up.

Secret Mission 6 (5 points)
Use Raven's Serpent arte to stop the Gigalarva from healing.  If you 
haven't synthesized the Moon Selector (which lets you switch controlled 
characters in battle) you will need to control Raven the entire battle.  
After you've damaged the Gigalarva enough (usually around 50%), you 
will see it start moving over to the pond to attempt to heal itself by 
sucking water out of it with its tail.  As soon as you see it start 
walking over, quickly move into the middle of the pond and activate 
Serpent.  This will drop a trap where Raven is standing, and if the 
Gigalarva's tail hits the trap, you will stop it from healing for the 
rest of the battle.

Secret Mission 7 (5 points)

Destroy the bridge supports to stop Barbos from calling reinforcements.  
You can target the bridge supports like any other enemy, so quickly 
eliminate them before focusing on the other enemies or Barbos.

Secret Mission 8 (5 points)

Allow Zagi to charge his blastia until it explodes.  Set your entire 
party to defend and have Rita cast simple spells like Fireball.  This 
usually causes Zagi to use his Blastia Suction ability.  After using it 
4-5 times without being hit, you will get a scene that shows it 
exploding and he will lose the ability for the rest of the fight.

Secret Mission 9 (5 points)

Kill the Leader Bat before Pteropus can re-combine.  After doing some 
damage to Pteropus, he will split into several different bats.  Quickly 
have your entire party target and kill the Leader Bat before killing 
any of the others.  This will prevent him from reforming into Pteropus.

Secret Mission 10 (5 points)

Destroy Outbreaker's core.  During the fight, Outbreaker will attempt 
to heal itself and switch day to night (or vice versa) by spitting out 
its core for a brief period.  You can't target the core separately, but 
using attacks that hit things in the air (like Judith's Luna Rondo or 
Yuri's Savage Fang) will destroy it fairly quickly.  You will see the 
orb change color as you do more damage to it, and you don't have to 
destroy it before it changes the day/night cycle.  To quickly cause it 
to spit out the orb, hit it with a fire spell at night or a water spell 
during the day.

Secret Mission 11 (5 points)

Light all the candlesticks, dispelling Belius' double.  After you 
damage Belius to roughly 50% health, she will create a clone of herself 
and extinguish the 4 torches in the battle area.  Quickly target each 
one and use Yuri's Destruction Field ability to relight them.  They 
only stay lit for a short period of time, so you will need to quickly 
light them all at once.

Secret Mission 12 (5 points)

Knock Tison and Nan to the ground after their artes cause them to be 
momentarily stuck.  Each of them uses an attack that will cause them to 
momentarily get stuck to the ground - Nan's is a jump attack where she 
crashes her weapon down into the ground, while Tison's is an attack 
where he sticks his hands in the ground and summons up what look like 
fire dragons.  There is a brief period after these attacks where you 
will see them struggling to get free from the ground, during which they 
must be hit.  You need to see a "Great!" for BOTH of them to complete 
the secret mission.  I would recommend going for Nan first (as she 
heals herself and does her attack more often), then eliminate her 
before focusing on Tison's.

Secret Mission 13 (5 points)
Attack Schwann as he clutches his heart after executing his Mystic 
Arte.  Before going into battle, make sure you have the Recover skill 
equipped.  When you see Schwann go into Overlimit, be prepared for him 
to use his Mystic Arte which will send your party flying.  Stand near 
him before he executes it, and tap Guard as you're flying through the 
air to quickly upright yourself.  Then, run to him and quickly hit with 
him an attack.  Using Ghost Wolf or Azure Storm is good for this, as it 
can reach him quickly.

Secret Mission 14 (5 points)

Use Karol's Nice Recovery Smash to cure Zagi of poison.  Obviously, 
make sure Karol is in your party.  About halfway through the fight, 
Zagi will activate a poison cloud around himself.  Quickly either 
switch to Karol or order him to use Nice Recovery Smash near Zagi, and 
you will remove the poison from him.  

Secret Mission 15 (5 points)

Knock Baitojoh out of the water by hitting its fin 3 times during an 
underwater attack.  This must be done during the second part of the 
fight, where your whole party is fighting him.  You will see him go 
underwater, and shortly after his fin will appear.  You must hit it a 
few times during that specific attack; hitting it one time each time he 
goes into the water does not seem to work.  The damage you do doesn't 
matter, so an arte that hits more than once (like one of Rita's spells, 
i.e. Violent Pain or Stalagmite) can quickly get the job done.  If you 
are having trouble, try using Shining Dragon with Yuri or charge one of 
Rita's spells and hold it until it goes underwater.

Secret Mission 16 (5 points)

Use Mother's Memento to break Estelle's shield.  As I mentioned above, 
this item MUST be obtained before going to Myorzo the first time by 
sleeping at the inn in Mantaic.  During the second part of the fight 
(where Yuri is alone), use the Memento on her.

Secret Mission 17 (5 points)

Explode Yeager's heart by breaking his guard and hitting him with 
Raven's Rain arte.  This is the most difficult Secret Mission (at least 
for most people), and there are various strategies for completing it.  
Note that it must be done during the second part of the fight, where he 
reveals his blastia heart.

I recommend setting the game to Easy, as guard breaks seem to be harder 
to do in higher difficulties.  When he reveals his heart, go into 
Overlimit as Yuri and spam Destruction Field.  Take note of how many 
times you have to hit him with it to break his guard - you will know 
his guard breaks because you will hear a glass shattering sound, and 
will see him scream and clutch his chest for a couple seconds.  When 
you see him clutch his chest, quickly order Raven to use Rain (NOT 
Rainsong) and if Raven is front of him, you will see the explosion and 
get the mission completed scene.  Make sure you don't hit him while 
he's clutching his chest, as that will remove the animation and put him 
back into normal fighting stance.

If it doesn't work, Raven may not have been in the right spot, or 
sometimes it seems to cause an explosion even though he is no longer 
clutching his chest (this may be because guard break lasts longer than 
his animation does).  The other difficulty with this is that he may not 
guard, but rather just stand there and get hammered by Destruction 
Field.  It seems like most times, he will go into guard mode if you get 
him in the blast radius of activating your Overlimit, then quickly run 
to him and start using it.

An alternative strategy is to make sure Raven has skills equipped to 
boost Overlimit time, and control Raven.  As soon as the second portion 
starts, activate Overlimit with Raven and spam Rain until his guard 
breaks, and the next Rain will hit him causing the explosion.  This 
method did not work for me, as he would usually run around or just 
stand there getting hit by Rain without guarding.  Even when he did, it 
seems hard to do enough damage with Rain spam to cause the guard break.

Secret Mission 18 (5 points)

Strike at Alexei as he recovers from using his Mystic Arte.  This is 
very similar to the fight against Schwann (Secret Mission 13), and the 
same strategy applies.  Note that each time he uses his Mystic Arte, 
the time it will take him to recover is increased.

Secret Mission 19 (5 points)

Knock Gusios over by attacking its rear legs while it's standing on 
them.  This is similar to Secret Mission 5 (for obvious reasons), with 
the added caveat that he will NOT rear up on his hind legs unless you 
have hit him in the tail enough to cause his tail to retract.  To hit 
the tail, Free Run behind him and hit him a few times.

Secret Mission 20 (5 points)

Attack Khroma in the middle of her earthquake attack.  A couple of 
Khroma's moves involve her flying into the air, then crashing back 
down.  One of them will cause an earthquake that causes rocks to fall 
over the battlefield.  When you see her flying into the air, quickly 
get near where she will land, guard as she lands, then quickly hit her 
with a multiple hit arte like Yuri's Shining Fang.  If you do this 
whenever she flies into the air, you will get this fairly quickly.

Secret Mission 21 (5 points)

Allow Flynn to use every arte he has, including his Mystic Arte.  Make 
sure you go into the fight with your Overlimit gauge at least at 3 (or 
use limit bottles), then activate your Mystic Arte.  If you haven't 
used a Mystic Arte yet, you use them by going into Overlimit 3 or 4, 
hitting the enemy with an Arcane or Burst Arte, and holding down the 
Attack button (similar to how you activate Burst Artes by holding down 
the Arte button).  As soon as you activate yours, Flynn will counter 
with his own Mystic Arte and cancel yours.

After he uses his Mystic Arte, damage him to around half health so he 
will attempt to use his healing abilities.  Then, simply defend until 
he uses Holy Lance and the rest of his Strike Artes and you will see a 
scene indicating you've completed the mission.

Secret Mission 22 (5 points)

Strike Zagi as he recovers from using Blastia Bane.  The timing window 
on this one is smaller than others, so you will need to him very 
quickly after he uses the ability (but not during it).  You will see 
him reach his arm into the air and say "Come on Come on Come on!" as he 
activates Blastia Bane.  Fortunately, it seems like the more he uses 
it, the longer you have to hit him afterward.  Once you get a sense of 
the timing of Blastia Bane, you will know when to attack him so you hit 
him right as it completes but before he recovers.

Secret Mission 23 (5 points)

Defeat Duke using a Mystic Arte.  Note this means you have to kill him 
during the Mystic Arte, not just use one during the fight, and this is 
during his SECOND form, regardless of whether you unlocked the third 
form by collecting the Fell Arms.  Depending on your level and attack 
power, you will want to get Duke's second form down to around 25,000 
health remaining and set everyone to defend.  Then, activate your 
Mystic Arte (see Secret Mission 21 if you're unsure how) and make sure 
it kills him.  If not, use some Limit Bottles and try again.

Copyright 2008 Brian Rutherford.  
This guide may not be reproduced without my permission.