I might need time to think of the skills,so ill come back with the idea,all right?
I'm thinking of him being a support-based character.
Edit:I figure out a idea for all the skills.
Passive:Every time he hits an opponent or ally with a ability,they gain a exorcism charge(Up to a max of 3),enemies who have exorcism charges have lowered attack damage for a few seconds,allies with exorcism charges gain a small amount of life steal for a few seconds.
Q:He throws a exorcism slip that does some damage and goes through enemies and when it reachs the end of its path,it will stop and stay there for 5 seconds and reveals all enemies who walks through it for 3 seconds.
W:He throws a single slip in a straight line that shields any allies hit within its path.it can hit up to 3 targets in a single casting,adding a additional charge for each target hit after the first.
E:He throws 2 slips in a arc similar to Diana's q,any enemy hit will be damaged and slowed,with a stronger slow if they both hit the same champion,it does not,however boost how much damage it does.also,if both hit,they get two charges instead of one.
R or Ultimate:He will burn away all exorcism charges,doing one of the following effects to enemies equal to how many charges.
1.Damages them for moderate amount
2.Damages them for a slightly higher amount and slows them for 2 seconds
3.Damages for a slightly higher amount than two,and stuns for 0.75 seconds.
For allies with them,they are healed,with better effects the more on them.
1.Heals for a small amount.
2.Heals for a slightly higher amount and boosts the champions armor and magic resist slightly.
3.Heals for the same amount of health as 2,and slightly boosts armor,magic resist,attack damage,and ability power.
Hopefully it isn't too overpowered of an idea.