An ability kit that would fit a witch or some kind of black magic champion.
Im terrible with names and honestly i think i might sound cringe if i try to make one so ill just keep it simple.
Passive: Curse
Everytime a champion dies, a large zone is formed around their death location for 30 seocnds. If the champion is an enemy, you gain ability power and 5% cdr while in the area. If the champion is an ally, you gain armor and magic resist while in the area.
Each zone you enter permanently grants 5 maximum health, up to 250.
Q: Hex
Hex a target, which activates after 1.5 seconds and can be detonated with your next spell to deal bonus magic damage and an effect based on the ability. (Lasts 5 seconds.)
If not detonated within the timeframe, the target will be hexed for 90 seconds. If all living enemy champions are simultaneously hexed, the hexes will detonate and deal (large amount of magic damage.) This attack is unstoppable, meaning it cannot be negated by spellshields/untargetabilities/windwalls, etc. (Exceptions: stasis.)
Additional Note: Hexing a new target extends the duration of all active hexes by 10 seconds.
W: Astral
Cause an explosion at the target location, dealing (amount of magic damage) to enemies over a large area and slowing them by (small amount) for 2.5 seconds.
HEX: Enemies affected are revealed with true sight for the duration of the slow.
E: Malice
Toss an orb in a direction, latching onto the first champion it hits. After 1 second, the orb will explode for (magic damage) in a moderate area to enemies hit.
HEX: Enemies affected are knocked away from the area and briefly stunned.
R: Reanimate
Channel for 1.5 seconds to revive a dead allied champion's corpse. The target will recieve 500/750/1000 (small ap ratio) health and mana upon revival and will be immune to crowd control for 0.25 seconds (to prevent bullshit.)
NOTE: Reviving the ally will not undo anything caused by the kill, like experience + gold gain or KDA. If the ally died with a bounty it will not be restored.
I really like the first ability because it's like a "slow buildup" ability in which you "charge" and then blow a devastating attack.