Can I use Last Breath to ready an exhausted unit in base, then move it to the battlefield to trigger Mask of Foresight's +2 bonus before Last Breath deals its damage?

Ruling: No, you cannot move the unit to trigger Mask of Foresight before Last Breath deals damage. Once Last Breath begins resolving, the entire effect (ready the unit, then deal damage) must complete before any other actions can be taken.

Sequence:

• Last Breath begins resolving
• The unit readies
• Last Breath deals damage immediately
• Only after Last Breath fully resolves can you take other actions

Nuances:

• You can use Yasuo's move ability BEFORE playing Last Breath to move the unit to the battlefield first, which will trigger Mask of Foresight on its own chain, then cast Last Breath afterward with the +2 bonus already active
• Even if you tried to use a spell to move the unit while Last Breath is resolving, any triggered showdown would be staged and wait for the game state to be open