Amumu + Frozen Heart doesn't take damage from minions
My friend figured this out, tested it many times and it works. 
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5 Comments
Why not? It's just 100 armor. I don't think this is true.
I guess this'll be the thread that disables amumu due to a game-breaking bug lol
Have you tried this without putting any points into E?
If you get enough armor, it's quite possible that the minions' damage is being reduced enough that Tantrum's passive blocks it entirely. I can't remember if it reduces the damage pre-mitigation or post-mitigation.