There’s no lag in heart of the mists, but every time I join a PvP game (any game) I get this annoying 1 second delay on all my skills.
I noticed this happens to me every time the pvp gets popular and people actually play it. I don’t have any kind of lags in the periods where the game is “dead” (i.e., long queues, few people playing) or off peak hours.
As far as I know it doesn’t affect everyone, but it is a really huge issue for some of the players.
Note: I don’t lag in any other game, and my conection is 88.44Mbps download, 9.77 Mbps upload. I’m playing from spain.