How to get the final 2,174,483,560 highscore?

[fractalman]

You sure that's not a chapter 0 score? i know some people with scores that high there...
if it's chapter 1, though, that's hacked.

the only semi-legit way takes too much time, even if the mana pool is unlimited (I am unsure if this is the case in chapter 1); on the final level set up lots, and lots, of cyan gems with <160 damage, and several orange gems with <160 damage, as well as a few blue gems. NO purple gems...or you'll kill it too soon.
then, just use the mana spell...oh, a million or a billion times, and chuck gem bombs, or upgrade the towers, or place the pseudo-prismatic supergem with 10,000 firerate you've been making for fun.
again, this only works if the mana pool size is unlimited.