Helltides spawn every 2 hours 15 minutes, and last for 1 hour.
NEW FOR SEASON 2 - Living Steel Chests (280 embers) are needed to spawn uber bosses. The pink chests are the locations.
During Helltides, there are mysterious chests (green chests below) that cost 250 embers. They refresh on the hour.
Dedicated page @ /events/helltides
Helltide spawned @ , ends @ , next one @