In the latest edition of Splatterhouse for the PS3 and Xbox 360, you can unlock a secret missions in the Survival Mode Arenas. Beating these secret missions will unlock bonus weapons for that arena.
To unlock secret missions for a Survival Mode Arena, complete the tasks below:
Go 1 minute without taking damage
Go 2 minutes without taking damage
Kill 25 enemies in berserk mode
Kill 50 enemies in berserk mode
Kill 10 enemies with body parts
Kill 25 enemies with body parts
Kill 5 enemies with splatter kills
Kill 20 enemies with splatter kills
Step on 20 Boreworms
Step on 50 Boreworms
