There is a slight problem with pacifist mode. To enter pacifist mode you can't attack or revenge anyone, that part is fine. But if you defend yourself from an attack, pacifist mode is turned off. You should be able to defend yourself from a pending attack and still retain pacifist mode.
I think the "Showdown" level is just meant to kill you. I tried surviving it with 45 blade towers 100% maxed out and I could only kill about 10. I also had about 20 money towers and a few slow towers along the way. "Showdown" basically means Game Over.
Overall, I liked it. The only problem I saw was that the tank was a little hard to move some of the time. But other than that, the upgrades were good, there was a decent amount of enemies in each round, and most of the bosses were tough and rewarding. I gave this game 5 out of 5.
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