When loading a save all abilities go on cooldown for some reason even if they weren't when the save was made. This often makes saves useless for any defense reliant on abilities since they'll immediately fail being unable to use them on whatever wave they happen to be on.
For any Capture the Flag map, assassin smoke bomb teleports won't make you drop the flag, and can even teleport you directly to your own flag... or into the enemy team. It's useful for challenge 11 if you're caught in a never ending stalemate like I was.
Once you get engineers it's possible to just spam scouts down whichever lane they didn't send any units in and then spam engineers once their base camp is destroyed and still end with a "perfect" score.
Many of the alien levels, especially deathmatches feel like 5vs1s where the enemy team can kill two of their own guys for points.
I believe I'd do much better without my... "teammates".
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