REDU format ruling
Multiple Piece Golem

Nearest-era rulings (Tengu, Sept 2011) — no REDU-specific archive exists.
Card effect (current official text)"Big Piece Golem" + "Medium Piece Golem"
At the end of the Battle Phase, if this card attacked or was attacked, you can return it to the Extra Deck. Then, if all of the Fusion Material Monsters that were used for the Fusion Summon of this card are in your Graveyard, you can Special Summon them.
Rulings
- Multiple Piece Golem's effect is a Trigger Effect. It does not target.
- Multiple Piece Golem is returned to the Extra Deck when its effect resolves. Returning it is not a cost.
Rulings data courtesy of Format Library — formatlibrary.com. Spotted an inaccuracy? Flag it in the REDU forum — sourced change requests get reviewed.