Once per turn: You can discard 1 card; add 1 "Polymerization" from your Deck or Graveyard to your hand. Once per turn, during the End Phase: You can target 1 monster in your Graveyard that was used as a Fusion Material for a Fusion Summon this turn; add it to your hand.
The problem with a field spell is that for fusion there's a good field spell, fusion gate, even though it does banish your cards, I still think it's better, because you don't need to discard a card, and then you can keep fusing without restrictions
Just keep bringing back the "immortal dragon" via Red Eyes Insight, Red Eyes Spirit, Cards of The Red Stone and Red Eyes Wyvern combos. Coupled with Branch! having this card would make for an amazing fusion deck.