It means they got a triple. So maybe dont level up tavern that turn *if you're facing them because they could be coming at you with the heat.
*conversely if the other emblem comes up (maybe you mean this one) which announces they leveled up tavern, it is often safe to level your own if you think you can beat them. Building more face damage isn't the best strategy.
3
I like this Deck. Ok, the winrate could be better, but it feels solid to play it and it is fun to play.
Only thing I changed: I replaced Nozari with Alexstrasza. I don't really like Nozari. To play it effective you need to play a good High Priest Thekal in a situation, where your opponent did not take to much damage till round 10 (otherwise you will heel him to full health as well). It is to unlikely to play a really good Nozari.
And, as we all know, it is a general ruel in Hearthstone, that every Dragon Deck comes along with Alexstrasza. You know, each hero starts with 30 live, your deck has 30 cards and a Dragon Deck will always have Alexstrasza. Also, for every new player, who is considering which Legendary card he should craft first: Alexstrasza! Alex is able to heal you up with a maximum of 14 or to deal a maximum of 15 damage to your oponenent. And you will get a 8/8 body for 9 mana, which is it worth as well.