Advanced format ruling
Instant Fusion
Card effect (current official text)Pay 1000 LP; Special Summon 1 Level 5 or lower Fusion Monster from your Extra Deck, but it cannot attack, also it is destroyed during the End Phase. (This is treated as a Fusion Summon.) You can only activate 1 "Instant Fusion" per turn.
Current rulings for this card are maintained by Konami.
Rulings data courtesy of Format Library — formatlibrary.com. Spotted an inaccuracy? Flag it in the Advanced forum — sourced change requests get reviewed.