Played a few runs. The run-2 hook is the strongest idea I have seen in this jam: the ember that ended you comes back cold, at the spot you died, and catching it pays you back. Turning a death position into something the next run remembers is genuinely good.
One source-level thing that will bite players: the catch zone is asymmetric the wrong way. reachL = foxW()*1.05 behind the fox, reachR = foxW()*0.56 in front, but the fox's head is on the right. So you get a bigger magnet behind the tail than in front of the snout, and players will feel "I was right there" on right-side misses. Swap them or at least equalize.
Fire drain and the spawn ramp feel well tuned, and the low-fire heartbeat tone is a great tell. gg.