Tim, Mermaid of the Deep

Aquatic Adaptation — Tim, Mermaid of the Deep can’t be blocked by creatures without flying or islandwalk.
Reflective Surface — 1GU, Tap: Target creature becomes a copy of Tim, Mermaid of the Deep until end of turn, except it’s not legendary if you control more than one creature named Tim.

"The sea lends me a tail, just as my friends lend me their dresses. Both fit surprisingly well."