The dis is an elite creature of the Fortress in Might & Magic: Heroes VII add-on, Trial by Fire. Its upgraded form is the valkyrie.

Their ashen body sporting majestic wings of fire, Dísir are manifestations of Arkath. They are born on the battlefield, when numerous Dwarves die in battle. Their souls then gather and, with Arkath’s blessing, they spark this powerful warrior spirit into life. OffBck


Soulfire Soulfire
Adjacent friendly creatures get the buff "Fiery Soul" (even when just passing the creature), increasing their base damage and movement until the end of the next turn.
Adjacent friendly creatures get +15 Morale and +2 Movement (even when just passing the creature).OffBck


Basic creatures
Defender · Bear · Kobold scout · Dis · Rune priest · Lava elemental · Fire giant · Red dragon
Upgraded creatures
Shieldguard · Blackbear · Kobold pathfinder · Valkyrie · Rune patriarch · Magma elemental · Einherjar · Ardent dragon
Warfare creatures
Runestone - Dwarven ballista · Fire cannon