After receiving a battle bond greninja from fishing, I trained up its EVs and leveled it up. However, later when i visited the summary screen, the ability appeared and functioned as torrent. Between the two events, it received the Pokerus virus, was "mega evolved" outside of battle, and used the ability in battle with another player. It also fought an NPC, during which the match was forfeited, in case any of these details help.