Minecraft: PlayStation Vita Edition

Before you go and revive the Ender Dragon, don't forget to take an empty bottle with you, when the dragon spits out purple fire, collect "it" from that place

Well, here you just need to take an empty flask and at the edge, when the dragon spits a ball, from which after the explosion a poisonous cloud will remain, scoop up this cloud with the flask. you can also take the dragon's breath when it flies to the center