Yi and Yasuo
Basic attacks alone can do 900 damage when they crit. (as much as some burst mage attacks) But when an ability that has its own base damage and can strike multiple targets gets to crit, that's unfair. Simple solution: Don't make abilities that crit. When a champ can deal that much AND attack super-fast because a crit item is also a huge speed item, they don't need to get an ability that scales with AD and can crit.