Ok, I get it - you're not running with real-time people, it's more like it picks 4 or 5 recent runs by people and then downloads them and plays them while you run (like ghosts). I was thinking it was quite a feat to pull this off in real time, but when I started seeing my own name popup, I understood what it was doing.
If you have a good solid team and you're getting bored marching toward 150 on casual, grab ch3at 3ngine 5.5 and blast the speed up to 4. This lets you clear an entire level in 60 seconds. The enemies will come at you really fast, but this is assuming your team can handle most anything (and have leech mods on some weapons just in case)
64 isn't that bad if you have your points right. Be sure to eliminate the armor, middle tower blocker, and health glyph after you get your first tower setup and gemmed. Never call waves early. It's not too bad after I tried it a few times, but I think it's about your point placement on that one.
The challenges are pretty, uh, challenging. For some, you basically have to play the card that makes him go insane, then hope he gets meglomania then stay alive long enough for that to eat him alive.
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 "Quick Switch"){kind=icon}
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 "Achievement Unlocked 3"){kind=icon}
 "Edmus"){kind=icon}
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 "Pixelvader"){kind=icon}
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 "DropSum v2"){kind=icon}
 "Off The Rails"){kind=icon}
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