Rainbow Neos [PTDN-EN044] Secret Rare OTS Tournament Pack 8 or monster effect is activated:

or monster effect is activated: Send 1 face-up "tellarknight" monster you control to the Graveyard

You can remove from play all other DARK monsters you control and from your Graveyard to have this card gain 500 ATK for each card removed

you can Tribute 1 other Fish-Type monster to negate the effect and destroy that card

you can Tribute 1 monster to inflict 1000 damage to your opponent

and Set this card face-down again instead of sending it to the Graveyard

Rainbow Neos [PTDN-EN044] Secret Rare OTS Tournament Pack 8 or monster effect is activated:Set: Phantom Darkness Card type: Fusion Effect Monster Rarity: Secret Rare Attack: 4500 Defense: 3000 "Elemental Hero Neos" + "Rainbow Dragon" or "Rainbow Dark Dragon" This card cannot be Special Summoned, except by Fusion Summon with the above Fusion Material Monsters. Once per turn, you can activate 1 of the following effects: Send 1 monster you control to the Graveyard to return all monsters your opponent controls to the Deck. Send 1 Spell or Trap