Nanogene Conversion

Choose target creature you control. Each other creature becomes a copy of that creature until end of turn, except it isn't legendary.

True Polymorph

Target artifact or creature becomes a copy of another target artifact or creature.

Echocasting Symposium

Target player creates a token that's a copy of target creature you control.
Paradigm (Then exile this spell. After you first resolve a spell with this name, you may cast a copy of it from exile without paying its mana cost at the beginning of each of your first main phases.)