Greninja is rarely encountered in Paldea, and the Greninja that appears during this event has Poison as its Tera Type.
Greninja, otherwise known as Ninja Pokémon, is a dual-type Water and Dark Pokémon introduced in Generation VI.
The first round of the Unrivaled Greninja Tera Raid event will begin on January 27th, at 00:00 UTC until January 30th, at 23:59 UTC.
The Level 100 Greninja will have its Hidden Ability, max IVs in every stat, and the unique Mightiest Mark. It is also likely that this Greninja has access to the powerful Water Shuriken move, as well as the Battle Bond Ability.