You can pay three mana to give all of your creatures +1/+0 until the end of the turn, but the main ability is that Purphoros will deal two damage to each opponent every time a creature enters on your side of the battlefield
Plus, getting five monsters onto the field is an arduous task, and getting a beatstick for having those 5 + a Ritual Spell and a Ritual Monster who have been dead in your hand for who-knows-how-long is not good enough a reward for it (especially when you're losing damage output for the beater as well as card advantage)
The tremendous flexibility of this card to take out whatever is posing a problem for you is invaluable, and there is little doubt many will take advantage of it, but this isn't quite the card its predecessors were
While Terra can take some work to make her truly effective, the precon already offers an excellent start with some incredibly powerful combos and consistent value returns
If a token is exiled with Haytham Kenway's last ability, it will cease to exist and won't return to the battlefield