Trick, known in the 2009 Christmas event as Scare, was the emote released with the 2008 Hallowe'en event. Upon using it, the player will lift his/her hands and bats will release. It was first released by looking into Maggie's cauldron. Apart from this emote, you can additionally unlock the Zombie Hand and Scared emotes if you have not previously done so during previous Hallowe'en events.
Trick was the first emote used in a holiday event. The 2008 Hallowe'en event required players to learn it, or they couldn't finish with the event. To get the candy for the witch, players would get a random choice of just getting the treat or having to perform a trick to scare the person handing out the candy. Without using the trick emote, players would just say "Boo!" and not get any candy.
Trick emote sound.
This is the first ever emote with sound in the free-to-play version of RuneScape.
The emote received a hidden update on 7 October 2009, resulting in a much smoother emote. Noticeable changes includes bats flying at a slower speed upwards, and frame tweening. The bats' wings seem to flutter differently too.