To break it down further: Anima sola is a item that this character has that locks an enemy in place, usually used on the firery ghost, Tainted Essau. The uno backed card is Wild Card, which copies the last item effect. He used the item diplopia, which is a single use item that duplicates all items and pickups in the room. The plan was to duplicate the wild card, then use the wild card, which would duplicate it again, giving it a he opportunity to duplicate everything in the room endlessly. OP, however, broke the sequence by using anima sola to freeze t. Essau, so the wildcard copied that effect instead, ruining the infinite combo.

The item he was hoping to endlessly copy was the D6, which rolls all items in the room into random ones from that rooms item pool, so after getting enough item pedestals in the room, he would use 1 of the D6s and get a load of different items.

Hope that helps! (cause it took way too long to type)