As two actions, you touch a creature and grant it a measure of protection from death.
The first time the target would drop to 0 health as a result of taking damage, the target instead drops to 1 health, and the spell ends.
If the spell is still in effect when the target is subjected to an effect that would kill it instantaneously without dealing damage, that effect is instead negated against the target, and the spell ends.
You can expend 1 additional mana so the target gains 3d10 temporary health when it drops to 1 health.
You can expend 1 additional mana so you can cast this spell as a reaction, which you use when a creature within 2 meters of you takes damage.