Apply these effects in sequence, based on the number of banished Fish monsters.
? 1+: Your Fish monsters cannot be destroyed by battle this turn.
? 4+: The activation and effects of Fish monster effects activated on your field cannot be negated this turn.
? 8+: Special Summon 1 Fish Synchro Monster from your Extra Deck. (This is treated as a Synchro Summon.)
You can only activate 1 "Ghoti Cosmos" per turn.