The 50-death-achievement is quite annoying. I had to just "startgame-die" approx 30 times after I had finished all the other achievements. And I don't think of myself as a particularly good gamer.
The 3 ways I know to weaken a Grinder enough to kill it with 5(?) blows:
A. Have it roll over Meltie-acid
B. Have two Grinders bump into each other.
C. Throw the Grenade-reward at them.
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