So I was playing a veteran player with one of those item dropping killer decks and I decided I needed to fill my more humble jungle/fire deck with Smash traps (next item dropped is destroyed.) I happened to have two on the board when my opponent played an item and although the item was burned, both my traps went up in smoke with it. So is that how counter traps work in this game? If I had 2 Mesmers on the board for example then both would activate on the next spell my opponent played?
Traps that apply to minions (unless lane specific) all trigger as soon as a minion is played (which means multiple lost at sea traps all fire at once - along with poison darts, cinderbox, and unnatural gas. Except for backfire, traps vs spells fire one at a time. All smash traps fire at once. I could be misremembering, but I also believe all essence jar fire at once. I have not tested multiple scavenger traps.
While the minion traps firing at once is a good idea -- really necessary for balance, I wish smash and essence jar worked like mesmer and spell net.
Well in my case even if they would have triggered one at a time it would not have made a difference at that point since the opponent had already generated a gazillion power points and had like a 4-1 minion edge.
I suppose the rule is logically consistent: spells are a one-off thing so they can be countered with less effort. Cards that stay on the board for multiple turns like minions and items should require more effort to counter. Given that, I would guess essence jar behaves in a way similar to smash then.