Charmer Quartet in Bloom

Per-phrase breakdown

• 2+ monstersGains 300 ATK for each different Attribute on the field. (Continuous)
• Once, while this card is face-up on the field, during the Main Phase (Quick Effect): You can target 2 monsters in your GY with the same Attribute but different Types, or with the same Type but different Attributes; Special Summon both, also until the end of the next turn, this card and the Special Summoned monsters cannot be used as material for a Fusion, Synchro, Xyz, or Link Summon. (Quick)
• You can only use this effect of "Charmer Quartet in Bloom" once per turn. (Condition)

Judge-facing facts

• The ATK-gaining effect is a Continuous Effect.
• The Special Summoning effect is a Quick Effect.
• You can only use the Special Summoning effect of 'Charmer Quartet in Bloom' once per turn.

Card-specific notes from database

• If one of the targeted monsters is no longer a valid target at resolution, neither monster is Special Summoned. (Konami neuron)
• The restriction preventing this card and the Special Summoned monsters from being used as Extra Deck material applies as long as the activation or effect is not negated, even if the Special Summon is unsuccessful. (Konami neuron)
• If this card or the Special Summoned monsters are no longer face-up in the Monster Zone, the restriction preventing them from being used as Extra Deck material is removed. (Konami neuron)
• Monsters restricted from being used as Fusion Material by this effect can still be used for Special Summoning procedures that are not Fusion Summons, such as 'Chimeratech Fortress Dragon'. (YGOResources)
• If this card leaves the Monster Zone (e.g., temporarily banished or moved to the Spell & Trap Zone) and returns, its 'Once, while this card is face-up on the field' effect can be activated again, subject to its once-per-turn restriction. (YGOResources)
• If control of this card changes after its 'Once, while this card is face-up on the field' effect has been used, the new controller cannot activate the effect again while it remains face-up on the field. (YGOResources)