Survive until the end of level one.
Survive until the end of level two.
Survive until the end of level three.
Survive until the end of level four.
Survive until the end of level five.
Complete a level with three stars.
Complete all levels with three stars on normal mode.
Survive until the end of a level while on hard mode.
Survive until the end of level six.
Survive until the end of level seven.