Critter Cages only work about 80% of the time. You may have to throw more than one. And yes, they catch almost all types of critters, including dragons! Handy against creepers. Warning though… they work better on some critter than others! Just throw one at an entity/mob to catch it. Right-click it on the ground to release the captured critter. No, critter cages do not work on Robots. Yes, they work on big critters too, but very rarely.
WARNING: DO NOT USE ON TAMED PETS! Being stuck in a cramped little cage messes with their heads and they will UN-tame!!!
Materials: 4 iron ingots and 4 sticks OR 4 crystal shards and 4 Pink Tourmaline