a bit anti-clamitic
not bad for 72 hour challenge. a few things i would add if you update or make another game.
power-ups. granny can throw the pan, or a temp. double damage.
a counter (more then the levels at the bottom) that lets you know how many targets are left in the respective wave. also, instead of breaking up the targets by waves, chain them together for a little bit longer of levels.
a score based system, number of cookies times total number of targets killed plus points for each kill.
hit points bar for the "boss" i was guessing to when i would be done killing it.
this is just the tip of the iceberg. good solid game for the time that was allotted.