To reach 300m in 30s on the red planet (powerful red) you need (everything max upgraded):
-H3 wasp
-D3 whirl
-B5 nova
-E5 furious cyclops
-T4 refrigerator
-S4 power booster.
Then just hold up button and enjoy the hard achievement
Ok if you can't manage boss 3 (the spider) on insane mode, try to disable player 2 if you enabled it. It only makes bosses harder to beat.
Then choose accessories that focuses on rate of fire and lucky strike and bullet count.
37 kills in the gauntlet thanks to SkylerFlight:
"32 Kills in the Gauntlet for me. Start by completing every level in the main campaign (all of the very hard levels). An all firebug team worked wonders for me here (spotted x2, spiny, commander, pyro, inferno). Then I went into the Gauntlet with an all Yellow team (nurse, orderly, doctor, esther, gunner, newbie). In battle, focus on stunning as many snails as you can each turn. This will prevent the enemy from attacking and allow you to build up yellow blocks. Also, Turn off auto attack and fight strategically. Don't over-hit an enemy. ester got up to 16 damage before I lost. Hope this helps!"
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