Easy "TAP HERO" Achievement
Complete level 300 then start a level between 1 and 49 (depending how much damage you can do) in order to instantly kill enemies. If done correctly, you will be able to kill about three enemies per second. The game must idle in this state for at least 100 hours. The game cannot be minimized and must have focus. After each day, spend your accrued gold on upgrades to allow the next day to be played at a higher level to allow faster progress.