I'm not sure I like the criteria you put to define a skiil. I think instead you should go with a more technical grid and try to make all possible combination

1. Targeting type ( (Delayed) Line Skillshot, Targetted Ability, Delayed Aoe Skillshot, AoE Around Player, Closest Enemy or Ally Target, Cone Skill Shot, Self Cast)
2. Dammage or not ( Yes or No)
3. Dammage Type (if Yes) (Magical, Physical, Direct, %HP, Mana Burn.
4. Buff Type (Heal, Speed Buff, Attack or Magic Buff, Armor or Magic Resist Buff, Mana ''heal'')
5. Debuff ( Same as buff but inverted)
6. Crowd Control (Stun, Slow, Snare, Push, Pull, Exotic target moving, Fear, Silence, Charm, Taunt)
7. Special Effects (Gap Closer, Invisibility, Stacks, etc...)


I think you will achieve alot of skills very fast with that. Yes they will be sort of generic but you still have the posibility to make Thousands of Skills with that and they can be relatively original. Anyway you will always need to keep a sense of familiarity so that people can learn your champions fast enought.

Name - Drain soul

Effect - Buffs self while debuffing the target, and draining some health and mana. The damage to the enemy scales to the enemy (i.e. percentage X%)
Type - Fear(?)
Changes Per Level - The amount the caster is buffed, and the proportion the enemy is debuffed

Name - Entangle
Effect - Target player is slowed by a good amount and damaged.
Type - Fear(?)
Changes Per Level - The range, damage, and length of the slow.

Name - Darkness
Effect - Target cannot see anything beyond a certain distance.
Type - Fear(?), AoE
Changes Per Level - How long it lasts.

Name - Intimidate
Effect - Caster cannot be harmed by anyone within a range while the spell lasts, and those within a range are slowed and life-drained, while being dealt extra damage. Spells are also more effective.
Type - Fear(?), Ultimate
Changes Per Level - How long it lasts, how much they're slowed, life drain, range



By the way, would you consider giving some skills an advanced version (i.e. an extra effect) that can be activated by certain spells (i.e. a spell that makes the next spell improved), which would also allow for more interesting combos? I'm personally not sure how practical it would be though.

Name - Aggro
Effect - For a while, the target player cannot see anyone other than the caster unless he is attacked.
Changes Per Level - How long it works.
Other - This is more effective than re-targeting and this is also more realistic. Also, the player will not be automatically alerted unless he becomes suspicious or checks his debuffs.

I'm not sure I like the criteria you put to define a skiil. I think instead you should go with a more technical grid and try to make all possible combination
1. Targeting type ( (Delayed) Line Skillshot, Targetted Ability, Delayed Aoe Skillshot, AoE Around Player, Closest Enemy or Ally Target, Cone Skill Shot, Self Cast)
2. Dammage or not ( Yes or No)
3. Dammage Type (if Yes) (Magical, Physical, Direct, %HP, Mana Burn.
4. Buff Type (Heal, Speed Buff, Attack or Magic Buff, Armor or Magic Resist Buff, Mana ''heal'')
5. Debuff ( Same as buff but inverted)
6. Crowd Control (Stun, Slow, Snare, Push, Pull, Exotic target moving, Fear, Silence, Charm, Taunt)
7. Special Effects (Gap Closer, Invisibility, Stacks, etc...)

I think you will achieve alot of skills very fast with that. Yes they will be sort of generic but you still have the posibility to make Thousands of Skills with that and they can be relatively original. Anyway you will always need to keep a sense of familiarity so that people can learn your champions fast enought.

For one thing, if you are properly going to include all the combinations, you're going to have a large number (7*2*5*5*5*10*3, and those are just some examples). That will also not include really creative ones. Finally, however, there will be a lot of overpowered skills as well as a lot of repititious skills that aren't special, mostly due to how what's really important is how the player would use the skill in the game.