I like me some
It goes in a different deck than the ones TrainmasterGT mentioned, but that doesn't mean it has no place in a cube. Others I like:
I feel TrainmasterGT should like the Death Ray, and Incendiary Flow > Volcanic Hammer
Fight with Fire is great in slower, controlling or rampy decks, where it can deal with a threat in the early game, or do a board clear plus some damage to the opponent in the late game. Pyrokinesis is a great tempo spell for aggressive decks, because you can use it to clear multiple blockers, all at no cost so you can deploy your board in the same turn. It's funny with the Heroes from THB (and
Feather, the Redeemed) as well. Pyrohemia is definitely not for the aggro deck, but great in red, controlly decks.
I don't think
fight with fire really counts as a burn spell- it's more of a cross between
Murder and
Fireball, both of which I would categorize into other groups. That said- it's a very flexible card and I think it's worth playing for the reasons you mention above. Removal+Finisher is a good combination for control.
I really dislike death ray in comparison to stuff like
Searing Blaze/
Blood because you're paying more mana for less damage output. Blaze does 6 damage for 2 mana while Blood does 5 damage for 2 mana. Meanwhile,
Super-duper death ray only does 4 damage for 3 mana. Also, you have to be fine with using silver border stuff if you want to play death ray, which a lot of people like to avoid. Cubes in the marked for a 3rd searing effect are probably happy with the death ray, but I don't think it makes the cut before Blaze/Blood except for in extremely low powered environments.
I don't like
Incendiary Flow all that much because the
volcanic hammer variants are lightyears worse than
Lightning Strike and friends, to the point where they only are cards burn decks would want. Because of this,
Incendiary Flow's exile clause is usually irrelevant and confuses drafters into thinking it's a removal spell and not a burn spell for face.
Volcanic Hammer is far more elegant in that regard. Given that
Incendiary Flow's upside is marginal and wordy, I think
Volcanic Hammer is the superior card from a design perspective. I feel the same way about
incinerate vs
Lightning Strike, but I think all of the instant speed 2 mana 3 damage spells are almost always playable, whereas I don't think the same is true for the sorcery speed variants.
Pyrokinesis is cool though. It's like
Fireblast meets
Force of Will .
I totally forgot to mention
Rift Bolt, by the way. That card is worth playing before any of the 1 mana for 2 damage burn other than
Firebolt and
Burst Lightning.