Historical Rules · 22 July 2016
Rule 701.34c
Official source text from the 22 July 2016 Rules release
If an effect instructs a player to meld cards that can’t be melded, they stay in their current zone. Example: A player owns and controls Midnight Scavengers and a token that’s a copy of Graf Rats. At the beginning of combat, both are exiled but can’t be melded. Midnight Scavengers remains exiled and the exiled token ceases to exist.