In the last GI magazine, they went over a few of the abilities in the game
There are two different trees - Harbinger and Necromancer. Each appears to have 19 skills. Harbinger is for melee, while Necromancer is for skills/their mastery. Tier-one cost 1 skillpoint. (1 ability) Tier-two cost 2 skillpoints (3 abilities) Tier-three cost 5 skillpoints (3 abilities) Tier-four cost 10 skillpoints (4 abilities) Tier-five cost ?? skillpoints (looks like 17) (4 abilities) Tier-six cost ?? skillpoints (looks like 22) (3 abilities) Tier-seven cost 25 skillpoints (1 ability)
Death Grip (1st tier Harbinger) - This crowd control ability summons a giant skeletal hand from the ground to hold an enemy in place while simultaneously providing a small amount of damage.
Weapon Master(2nd tier Harbinger) - This Harbinger skill causes Death's melee attacks to be critical strikes much more frequently and also makes critical strikes refill some of his wrath bar, allowing for more abilities to be used
Harvest (3rd tier Harbinger) - This ability increases Death's range by sending his Reaper form leaping forward with scythes firing out from it. Each additional skill point devoted to Harvest will cause more scythes to be unleashed
Improved Strength (3rd tier Harbinger) - Death's strength is increased +2. +2 per player level. His strength is further tempered in the forges of battle, channeling his energy of victory. Foes already feared Death, now they will fear his certainty.
Exhume (2nd tier Necromancer) - Coffins rise from the ground and burst open, producing small zombie minions who will fight for Death. Additional skill points allow more minions to be summoned at one time.
Murder(2nd tier Necromancer) - Death sends a large group of crows at an enemy. Like Death Grip, this causes some damage, but is primarily a form of crowd control, keeping bigger groups of enemies distracted so Death can focus elsewhere
Unending Hunger (?? tier Necromancer? Can't find it in the skill-tree image) - This passive improvement to Murder allows each bit of damage done by crows a small chance of producing another Murder. --- http://www.youtube.com/Ecwcwwe Currently recording "Let's Play"/Playthrough videos for: InFamous 2, Sly 3, and R&C3.