You can complete pretty much every map by spamming warriors (and building some golems when possible).
Food will be the main block, so focus os farm upgrades.
I used only the 1st character through everything.
Last stage is a bit tricker though, but still possible with just warriors and golems (and call of duty guys). Should win the game about the time he summons Armaggedon; if not, it may get harder after that, because of the black holes possibly eating your army suddenly.
Small (?) bug: if you fail and click on the X before it reloads, then enter again, clicking on circles won't move the lines. Reloading the page fixs it.
Bugged. On Hark the Herald Angels Sing, L note started gaining points without notes. After song, I can't click "next". The songs are cool, but the game per se is lacking many things, as people has already stated.
Dunno if someone else already said about these, but..
Bug: sometimes (didn't happen only once, the 1st wave on 8th stage), if you see some review page, the timer will reset. Great to make the game easier =p
Typo: "Perosixome" at the end.
Also, I had already forgotten many of these things =p
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