Does Sett, the Boss ready after conquering a battlefield when you've activated it in the showdown that made the conquer happen?

Ruling: Yes, Sett, the Boss readies after conquering a battlefield when activated in the showdown that caused the conquer.

Sequence:

• The replaced death (Sett's ability) happens first
• The conquer happens after
• Sett readies as a result of the conquer