"Gladiator Beast Bestiari" + 1 "Gladiator Beast" monster Must first be Special Summoned (from your Extra Deck) by shuffling the above cards you control into the Deck. (You do not use "Polymerization".) When this card is Special Summoned: You can target up to 2 cards on the field; destroy those targets. At the end of the Battle Phase, if this card attacked or was attacked: You can shuffle it into the Extra Deck; Special Summon 2 "Gladiator Beast" monsters from your Deck, except "Gladiator Beast Bestiari".
Can Special Summon 2 Gladiator Beasts from your deck.
Uses monsters on your field as material.
Must be returned to the extra deck if you want to use second effect.
Gyzarus can be returned to your deck to Special Summon Gladiator Beast Bestiari to destroy the opponent's back row and setup for another Gyzarus the next turn.
Gladiator Beasts have the unique mechanic of returning to the deck after battle and Special Summoning another Gladiator Beast monster. However, with the absence of Main Phase 2 in Duel Links makes them a lot slower than in the physical card game. Gladiator Beast monsters mostly gain effects when they are Special Summoned by other Gladiator Beast monsters.
Gladiator Beasts that have an extra Special Summoning effect are ideal for making their Fusion monsters. Gladiator Beast Anabata can Special Summon Gyzarus for free and still trigger its removal effect.
Completely OP fusion with its own protection that can be summoned with 1 card - no problem
Monster that can be summoned from the hand and can wipe the field and let you draw 1 card in either turn - meh
Gyzarus - OMG TOO OP THIS CARD MUST NOT EXIST