Military action
The ascension and subsequent destruction of Trympt, the Oathkeeper left the Betrayer Gods reeling, and with the relentless attacks from the Gods of the upper planes and their allies, the Betrayer Gods were left with very little time to recoup. Combined with the efforts of the Infernal Resistance in their own war camps, the Betrayer Gods are defeated. Some were killed, others were imprisoned, and many retreated on their own terms before they could end up like their less-lucky allies.