Burn the Accursed

What you pay five mana for here is finality, not five damage. Fair red cleared that damage rate years ago, and the two points to the controller are a minor aggressive tax on the side. The replacement is the reason to run it: any creature this spell touches that would die leaves the game instead, and the wording reaches deaths from any source that turn, not only the ones this spell dealt. That closes a door red is usually locked out of: no returning from the yard, no death trigger that feeds the graveyard, no delve or escape fuel left in the bin. It answers the threat fair red hates most, the creature worth more dead than alive, the one that keeps coming back or pays you for going. The cost of solving that problem is speed. At five mana the spell arrives long after the window where cheap burn wins a race, and it will never be the tempo play; what it trades that tempo for is certainty, a resilient or recursion-hungry creature removed cleanly and permanently at instant speed, on your terms. It is red conceding that killing a creature is sometimes not enough, and buying itself a way to make a death stick without leaning on white or black to do it.