Oni Token was a Legendary limited time currency that could only be obtained during the Red King Event and 50B Celebration Event. It was used for event-exclusive content and rewards while those events were active.

Obtainment:

The Oni Token can be obtained from several sources. It drops from Oni Soldiers (10 Tokens) and Red Commanders (300 Tokens), can be earned by rolling the Red Gacha (250 Tokens), or by exchanging Corrupted Fish with the Oni Fisherman. Fish exchanges reward 10 Tokens for Common, 20 for Uncommon, 50 for Rare, 100 for Legendary, and 200 for Mythical catches.

Usage:
During the Red King Event, Oni Tokens are used to craft the Shark (Corrupted) Fishing Rod, which requires 500 Oni Tokens, or to roll the Red Gacha, with each roll costing 250 Oni Tokens.