Power and Guard sources are possible. There isn't any for Magic and Mind source though.
About that opening the lid trick, I just read that in that other topic a few minutes ago XD. I'll guess I'll try that today with my PS2, never thought of doing that before, but it just might work. If that's the case, this could open a lot of possibilities. (Note: Battle Square, however, can it be applied though?) --- http://www.youtube.com/profile?user=KaddyGamer
i posted on that thread 2. you CAN DUPLICATE any non-battle item with the w-item materia, as long as you're already set to duplicate an item (how you make empty space 4 item your duping) b4 the item from battle is morphed or mugged (yes mug too)
you can setup morph or mug+counter 2 finish last enemy so all you do is wait 4 them 2 attack & die while your waiting in item menu.
normally when duping, you dont get rid of the item you wanna dupe. but here you do. when you use the item you wanna get rid of 4 duping sources or whatever, well now you can select your 2nd item or begin duping, but you used the last item right? wrong! just wait 4 enemy 2 b countered 2 death. when you get the item, right when it says item name, open the lid 2 prevent victory sequence.
if you waited on 2nd item in w-item menu, you can see that the item you morphed/mugged is where the 1st item (now empty since you only had 1) used 2 be. well guess what? the game doesnt duplicate battle items, it duplicates the number of items in the 1st selected space.
so say i morphed a power source, it will now be where my 1 hero drink (item i used) was. it will b grayed out since its not a battle item, but because it took the place of the usable item, it is now my selected duping item. but if you exit w-item menu, you have 2 start over with a new battle since you cant select the sources anymore. also, make sure you use all out of battle. trick only works when you dont have any of the item in your inventory b4 you start.
also works 4 mug as well, & you can just use the moves without countering, but you have 2 b fast. best way i found with this method is 2 use an attack that takes a bit of time 2 use, then have 2nd person morph/mug 2 kill (if you mug, you can obviously fail, so you just gotta try again), then have 3rd waiting in w-item menu 2 dupe. i can normally get that setup b4 my 1st person finishes casting matra magic.
i 1st tested morph method after watching video from the link in the other topic & found it to work. i thought mug could work so i tested it on adamantaimai during his counter i had barret ready mug & red XIII use my last potion, & had him select an ether. barret mugged an adaman bangle & killed him. i popped the lid & duped 99 adaman bangles.
AND GUESS WHAT ELSE!?!? i thought it could work elsewhere, & guess where that was? I mugged cursed ring from Ultimate weapon & opened case b4 as he flew off, screen stayed on where he left screen as i duped 99 cursed rings. when done i exited to command menu, closed the lid, & the battle ended a bit after that. now all my members have a cursed ring!