The horse sacrifice serves a similar purpose to the consecration ceremony that Yudhishthira held long ago, well before the Kurukshetra War. Like that ceremony, the purpose is to legitimize Yudhishthira’s rule, showing how ritual plays a role in acquiring and maintaining power. While Krishna lets many noble characters die, choosing not to offer a boon of resurrection, he revives Parikshit because it fulfills a prophecy and because Aśvatthaman acted foolishly in passion when he drew Brahma’s Head in battle, and so Krishna wants to partially counteract this rash choice.