In hunter, after you play Hydralodon and you end up with 4 Heads, if you play Devouring Swarm always the Hydralodon heats the enemy. Never the heads. I have never seen a head do it. Not in my games, not in enemies. I have never tested with 2 heads right after you play Hydralodon. Have anyone see a head attack?
Edit: Is this the right way to report a bug?
Devouring Swarm makes minions on the board attack a chosen target. The order is not random. Like almost every other interaction in Hearthstone, the order is determined by the order in which the minions were summoned. Hydrolon heads are summoned after Hydrolon is played, so the heads are always summoned after Hydrolon itself.
(Yes, I know that the visual effects seems to contradict this. That’s because the animation is shown at the end of the summon phase, but the attack order is based on the order of the start of the summon phase. Playing Hydralonon starts its summon phase; the Colossal effects summons the heads somewhere in the middle of the summon phase, and the animation of Hydralonon appearing is postponed until the end of the summon phase, after the heads have gone through there summoning sequence).
Once the minion targeted by Devouring Swarm has been dealt lethal damage, no further minions will attack it. So (1) Hydralonon always attacks before its heads; and (2) once lethal damage has been dealt no more attacks happen. In other words, if Hydralonon’s 5 attack value is enough to kill the target, then it is expected that the heads do not attack.
Yes, I have. After reading your post I created a deck to enable me to test this against the Innkeeper. I obviously had to wait until there was a minion on the board with more than 5 health, so that Hydralonon would not kill it. And I had to kill off my other minions. But once the Innkeeper gave me an opportunity, I did see a head attack.
Link to a replay of the game: https://hsreplay.net/replay/98P6fksLyK4XjiK84Bk7gv#turn=9a
Not really. This forum is for technical support. Bugs reported here might be forwarded to QA (testers) and/or devs, but I would not count on it.
The best place to report a bug is the dedicated Bug Report forum: https://us.forums.blizzard.com/en/hearthstone/c/bug-report/8
And if you do report a bug there, then the best way to do it is to (1) include a description of what you expected to happen and what happened instead; and (2) if you play with an add-on that records games, then add a link to the replay of a game where you noticed the bug; otherwise include a screenshot that shows the board state and your hand; plus some extra screenshots where you hover each of the recent icons in the history bar; plus the deck code of the deck you were playing. (A video recording of the game would work too, instead of the screenshots).