When Icathian Rain deals damage multiple times to a unit with 3 HP, does Seth's ability prevent death after each instance of damage, or does the entire spell resolve before death is checked?

Ruling: The entire Icathian Rain spell resolves first, dealing all its damage. Then during cleanup after spell resolution, the game checks for lethal damage and attempts to kill the unit, which Seth's Legend ability can replace/prevent.

Sequence:

• Icathian Rain resolves completely, dealing all 6 instances of damage
• After spell resolution, during cleanup, the game registers lethal damage
• Seth's ability can then replace the death