Collect all the Useless Relics.
Kill 1000 foes.
Complete all the levels.
Read all the signs.
Collect half the Useless Relics.
Kill 100 foes by roaring at them.
Collect all the Useless Relics in one level.
Kill 8 enemies with a single roar.
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Kill 200 foes.
Kill 25 foes by roaring at them.
Achieve all the hidden pixel mini-games.