Please feel free to add to this list if you know other spells that do not work as they should.
1. OK, this first one is not a spell and only happens in Mayhem. Enemy minions remain in battle after its caster dies.
2. Life hits are not boosting on myth minions.
3. Fire Minotaur's Tier 5 spell, 'Bargain of Brass', when given a blade to boost it, the blade boosts the hit upon the one casting it and not the enemies!
4. The Storm Elf spell 'Galvanize' is removing blades. This spell is not supposed to do that according to its description. If anyone else can confirm if this happens with 'Precipitous' as well, please do.