Right click to throw the card. Causes a explosion on impact (not damaging blocks). If it backfires, it will explode in your hands!
Right clicking will heal you four hearts. Backfires, however, will poison you for a few seconds.
Throw this card and hostile mobs will spawn where it hits. Good for ambushing other players. Be careful of backfires, as they will spawn the monsters next to you. The card will spawn either two zombies, two spiders, a skeleton, or a cave spider. All have an equal chance to be spawned.
For the sneaky ones. Gives you night vision, speed, and invisibility for 20 seconds. Enough time to sneak into your friend’s base or make an escape from attackers. Backfires will give you blindness and slowness for 10 seconds.
The fun one. A thrown card that hits another living thing will cause you to swap places with it. Use your mind, as this can be applied in all sorts of creative ways. Jump off a cliff then throw it at someone, dooming them to fall, or just use it to reach difficult places, etc. If it backfires, it will teleport you to a random location within 50 blocks.