Every few turns or so, the enemy hides inside a shell, making it unattackable and attacking the shell will cause an attack to happen.
Example of the Whelk:

I've got it set up to make the enemy reappear, but I'm unsure how to make it disappear in the first place (like a reverse appear halfway). Back in VXAce, there was the script fucntion that states the following that did this.
$game_troop.members[1].hide
However, this script function no longer exists in MV, simply giving an reference error stating that $game_troop is undefined. This is perhaps because of the move from RUBY to Java.
How would I go about hiding an enemy now?