Can I deathgrip a unit and save it with Sett legend power?

Yes, you can use Sett's legend ability to save a unit targeted by Deathgrip, but the Might bonus will not be applied to the second unit.

According to RiftJudge FAQ #9246, this interaction works as follows:

1. Playing Deathgrip: You play Deathgrip targeting a buffed friendly unit.
2. Resolution: As Deathgrip resolves, it attempts to execute its "Kill a friendly unit" instruction.
3. Replacement: Because the unit is buffed and would die, Sett's ability (a replacement effect) triggers to intervene. You pay the cost (exhaust Sett and pay [C]), and the unit is recalled to your base instead of being killed.
4. Condition Check: Because the replacement effect prevents the unit from actually dying, the "If you do" condition for the Might bonus in Deathgrip is not met. Therefore, you do not give the Might bonus to another unit.
5. Finalization: You still draw 1 card, as the card draw is not contingent on the kill.

Important Nuances:

• Replacement, Not Trigger: Sett's ability is a replacement effect, not a triggered ability. It modifies the event as it happens and does not use the chain.
• Buff Spent: As part of the cost for Sett's ability, the buff on the unit is spent (removed).
• Identity: Because the unit is recalled to your base rather than sent to the trash, it does not "die," so any "Deathknell" abilities the unit may have had will not trigger.