Endless mystery tonics are harder to reliably get than legendaries. I've personally opened over 700 black lion chests and only received only one of the three varieties. Such fun items should be reliably obtainable by those who want them most, and that is simply not the case right now. For this reason, I believe endless mystery tonics should either be made non-account bound (allowing one to buy them directly off the trading post from those who got them by chance and don't want them), or put directly in the gem store. If you want one of these awesome items, please sign this petition with your Guild Wars 2 username (ie. the name.1234 one)