Doomfist
Class: Tank
HP: 600, 300 health and 300 armor
Left-click: Doompunch - a melee attack with a narrow, but longer than normal hitbox that does 60 damage per hit. Punches can be thrown once every second.
Right-click: Rocketfist (cooldown: 7 seconds) - when activated, an arc with a landing point is shown in the UI. When cast with left-click, Doomfist takes 0.5 seconds to start launching himself, then flies through the air at roughly the speed Winston leaps. Press right-click again to cancel deploying Rocketfist - like Reaper's teleport. Enemies that are directly landed on take 100 damage, but Rocketfist otherwise has no AOE damage.
E: Inspirational Aura (cooldown: 5 seconds) - Doomfist activates one of his two auras, which is shown to allies as a translucent orb surrounding him. Inspirational Aura shows up as green. To enemies, the orb is invisible, but Doomfist's armor glows bright green. All of Doomfist's HP is immediately converted to health. All heroes inside the aura (including Doomfist himself) move 50% faster. When speed boosted, the enemy team sees heroes through walls as green dots. Press E again to deactivate the aura, which will trigger the cooldown. Switching auras also triggers the cooldown.
Shift: Protective Aura (cooldown: 5 seconds) - Doomfist activates his other aura, which shows up as yellow. To enemies, Doomfist's armor glows bright yellow. All of Doomfists's remaining HP is immediately converted to armor. All allies within Protective Aura take 50% less damage. The other 50% of the damage dealt to allies is transferred to Doomfist instead. Cooldown is triggered when the aura is deactivated, or switched to Inspirational Aura.
Passive: Harbinger of Doom - As Doomfist's HP lowers, he attacks faster. Every 150 HP lost, Doomfist attacks twice as fast. At 450 HP, Doomfist can punch twice every second. At 300 HP, he can punch four times a second. At 150 HP, he can punch eight times a second.
Q: Doomsunder - Doomfist jumps up and smacks the ground in an AOE around him (slightly bigger than Sombra's EMP), ignoring LOS. Enemies hit take 50 damage and are stunned for 1 second. Enemies deal 30% less damage for 7 seconds.
The radius of the auras is roughly the same as Mercy's beam length. Neither Lucio's speedboost nor Ana's nano-boost stack on top of Doomfist's buffs.
The idea with the variable health is to change Doomfist's roles on the fly. When he is speed boosting his team, Doomfist has 600 health, which we know from Roadhog can be very squishy. When he is protecting his team, Doomfist has 600 armour but he is literally taking damage for every member of his team. So while Doomfist offers very powerful buffs for his team, there are reasonable trade-offs for both. Moreover, Doomfist is a tank that needs to be protected just as much as he protects his team - for example, in Protective Aura the team within his aura has only 600 extra health shared amongst them and Doomfist still takes full damage if attacked directly.
tl;dr: Doomfist is a 600 HP tank. He has a melee attack, a Winston-like jump for mobility, and two auras. One aura provides a 50% speed boost, but makes you visible through walls. The other aura provides 50% damage resistance, but Doomfist soaks up the other 50% of damage. He attacks faster when hurt. His ultimate makes the enemy deal less damage.
