Otherworldly Survivor starts the game with
Many enemies will attack the survivor.
Survivor defeats enemies, and as you level up
and gain abilities.
When a survivor defeats a boss, a treasure chest will be dropped.
Survivor can gain abilities by taking the treasure chests.
The treasure chests have their own presentation, and the number of abilities
and the number of abilities earned from each chest is different.
After 15 minutes, there will be a big rush at the end.
How long can you survive?

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