[Zorak]

Update: as announced, all Dungeon Bosses will start as Dead in Istary. For transparency, I will leave here the exact times of death, and remind you of their set spawn timers:

Queen Ant: Died Tuesday 04, 19:06 (GMT -3) // 22:06 (UTC)
Core: Died Tuesday 04, 19:11 (GMT -3) // 22:11 (UTC)
Orfen: Died Tuesday 04, 19:05 (GMT -3) // 22:05 (UTC)
Zaken: Died Tuesday 04, 19:08 (GMT -3) // 22:08 (UTC)
Frintezza: Died Tuesday 04, 19:11  (GMT -3) // 22:11  (UTC)
Sailren: Died Tuesday 04, 19:10 (GMT -3) // 22:10 (UTC)
Baium: Died Tuesday 04, 19:09 (GMT -3) // 22:09 (UTC)
Antharas: Died Monday 15, 20:04 (GMT -3) // 23:04 (UTC)
Valakas: Died Monday 15, 20:02 (GMT -3) // 23:02 (UTC)

Dungeon Boss Respawn Timers
Queen Ant: 36h +/-1h
Baium: 168h +/-2h
Frintezza: 48h +/-1h
Orfen: 48h +/-1h
Core: 60h +/-1h
Sailren: 60h +/-1h
Zaken: 60h +/-2h
Antharas: 264h +/-2h
Valakas: 264h +/-2h
Beleth: 264h +/-2h