Fairly regularly (and especially in Black Lion chests) I seem to be given tonics whose description says will transform me into an ooze or a moa or what have you for 15 minutes. It also says I can't attack anyone but am, presumably, still vulnerable. I think I read somewhere that enemies will ignore you, but I'm not sure about that.
So my question is, what's the point of these items? If I can't attack anyone for 15 minutes that's a good chunk of XP I'm losing out on. I also can't interact with merchants. If enemies do in fact ignore you then they would be good for a quick escape from a tough battle, but 15 minutes is far too long for that.
The only possible use I can see for these is in a big fight with lots of downed players – you could transform and go around reviving people without fear of attack. Doesn't seem that useful. Am I missing something?
Best Answer
Tonics now have two additional uses (at least, during the Halloween event);
1) They can be consumed to be turned into a mob, which has combat abilities in the Costume Brawls, which also have their own achievement track.
2) Mystery Tonics are part of a recipe for the Mystic Forge, which allows you to create Mad King's Chests (no BL Key required!). Six Mystery Tonics, a piece of Candy Corn, and two different boosters (Killstreak, Karma, Regen, Magic Find, etc.) will create the Mad King's Chest. These chests have a chance to drop rare Halloween weapon skins.
Note: Now that the Halloween event is over, the Mad King's Chests are no longer available for crafting. They may or may not be implemented again next year. Mystery Tonics still turn you into various creatures that participate in costume brawls.