I was thinking about some variants of Chimera which targeted two cards:
Toxic Syzygy -- Pick two creatures. Create a new creature under your control with the sum of their stats (str and hp), and the union of their conditions, with an additional 2 poison counters.
Hybrid Vigor -- Pick two creatures you control. Each one is modified to gain the maximum of their stats (str and hp) and gain all positive conditions. Negative conditions which they don't share are removed.
Enforced Eidolon -- Pick two creatures controlled by anyone. The first one gains the max of their stats (str and hp), the second is set to the minimum. The first one gains all positive modifiers; the second suffers all negative modifiers.
Golem Pilot -- Pick one golem and one non-golem which you control. Remove both and create a new golem under your control. The new golem has summed stats (str and hp) and the active ability of the non-golem ingredient. Can target immaterial; do not copy modifiers except immaterial.
Bioelectric Feedback -- Pick two of your opponent's creatures in the same row. A bolt of lightning deals damage equal to the difference in their Str to all creatures between them on the field. You can't target immaterial or burrowed creatures, but the lightning will affect them.