Scuttling Sentinel
Creature — Crab Elf, {1}{G/U}{G/U}
Oracle Text
Flash
Vigilance
When this creature enters, put a +1/+1 counter on another target creature you control. Until end of turn, that creature becomes a blue Crab in addition to its other types and gains hexproof. (It can't be the target of spells or abilities your opponents control.)