You don’t need to control Creepy Crawler to make an opponent afraid of you. (Mechanically, I mean. Please don’t jump scare your opponents!)

Each time a Horror creature, Nightmare creature, enchantment creature, or face-down creature enters the battlefield under your control, all of your opponents become afraid of you for the rest of the turn, regardless of what happens to the creature that entered.

Similarly, each time a Horror creature, Nightmare creature, enchantment creature, or face-down creature you control attacks an opponent, that opponent become afraid of you for the rest of the turn, regardless of what happens to the creature that attacked. Attacking a planeswalker or battle, however, won’t cause anyone (your opponent or the planeswalker) to become afraid of you; most planeswalkers have seen some wild stuff.

Playtest cards aren’t legal for play in any tournament format other than Mystery Booster Limited formats. On the other hand, we expect they will spice up a wide variety of non-tournament games (as long as everyone’s on the same page about using them!).

Playtest cards use a modified version of game symbols, such as {T} and {W}. These modified symbols should be treated as the standard symbols during play.

For many playtest cards, you’ll need to make a generous assumption that basic game rules would be updated to allow them to work. The Mystery Booster 2 Playtest Card Notes section (reproduced here in individual Gatherer rulings) provides guidance for fitting these cards into the existing rules structure.