If a unit with 2 might is increased to 3 might with cleave, would it still die to another 2 might unit?

Ruling: No, the unit would not die. There is no separate HP in Riftbound - only might. When the unit is damaged, it would be 5 might (2 base + 3 from cleave) at the moment of being damaged, and damage would be removed before their might goes back to 2. Damage does not reduce might.

Nuances:

• Damage is marked on units but does not reduce their might value
• Temporary might increases are considered when checking if damage is lethal