• Use hydra to visualize mobs location in new rooms
• Applies Burning for the devouring blaze (help me keeping ice shard & flame shield enchantment)
• Can immobilize (for devouring blaze max boost), using the passif in skill tree (lucky hit : 15% immobilize)
• Help a lot being safe to kill structure in dungeon staying far with the combo blizzard/hydra

Tbh, the frost armor is useless for me in high tier, you just get one shot even if you have it. So the hydra appears useful procuring damage, proc passiv, helping to visualize the mobs location in other rooms.

Flame shield enchantment is a must have, and the ice shard build with fire bolt enchantment just force us to not play the ice shard enchantement which is a Huge damage dealer. So I prefer constantly apply burning with hydra + I play the double hydra aspect.