Simul Archfiends - 25th Anniversary Tin: Dueling Heroes Mega Pack (MP23)

This turn, neither player can Special Summon monsters with the same card types (Ritual, Fusion, Synchro, Xyz, or Link) they already control. If you do not control 2 or more of the same card types (Ritual, Fusion, Synchro, Xyz, or Link), all Ritual, Fusion, Synchro, Xyz, and Link Monsters you currently control gain 500 ATK. You can only activate 1 "Simul Archfiends" per turn.