A pause button would kind of ruin the pumped up feeling you get when you hear the music that lets you know you've passed 200 seconds... I think pause would be a bad idea.
It is impossible to beat level 100...
it's the air waves that doom you. With 20 lives, you don't have to kill all the creeps in level 100, but you do have to kill most of 93. Level 93 creeps have 104658 HP. Theoretically, it should take 21 swarm towers (the most cost-efficient air killer) to kill 14 of the level 93's, if they are at maximum freeze the whole way. 21 swarm towers costs $13440. The maximum money you can possibly earn until that point is $15140, which only leaves $1700 for the other towers, which you need to kill ground creeps in order to actually get all that money in time. $1700 is not nearly enough.
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