Vasal of the Seal vs Retainer

Overall comparison

HERO	Fraction	Element	Type	Rarity	Aura
Vasal of the Seal	Demonspawn	Force	HP	Legendary	HP 33% Place: All battles
Retainer	Dark Elves	Void	Defence	Rare	Defence 19% Place: Crypts

Stats comparison

HERO	LVL	STARS	HP	ATK	DEF	SPD	C.RATE	C.DMG	RESIST	ACC
Vasal of the Seal	60	6	21315	870	1288	98	15	50	40	20
Retainer	60	6	16185 -5130	672 -198	1277 -11	93 -5	15	50	40	0 -20

Skills comparison

Vasal of the Seal	Abyssal Seal Formula: 0.25*HP Attacks 1 enemy. Places a [HP Burn] debuff on the target for 2 turns if they are under a [True Fear] debuff or a [Decrease ATK] debuff. Also places a [Shield] buff on this Champion for 2 turns equal to 10% of their MAX HP. Shield HP Burn	Infernal Darkness Formula: 0.27*HP Attacks all enemies. Has a 75% chance of placing a [True Fear] debuff and a 50% [Decrease ATK] debuff for 2 turns. Cooldown: 5 True Fear Decrease ATK 50%	Daemon Possession Balances the HP of all allies. The HP levels of all allies will be brought up to the level of the ally with the highest HP. After balancing HP, grants an Extra Turn. Cooldown: 6	Legion of Doom [P] Formula: -0.2DMG_MUL Formula: 0.2DMG_MUL Receives 20% less damage from Champions from the Banner Lord, High Elf, and Sacred Order Factions. If there are 2 or more Demonspawn Champions on the team alongside this Champion, increases the C. DMG of all Demonspawn Champions on the team by 20%. [C. DMG increase only works when this Champion is alive.]
Retainer	Sundering Chop Formula: 3.2*DEF Attacks 1 enemy. Has a 40% chance of placing a 30% [Decrease DEF] debuff for 2 turns. Decrease DEF 30%	Resolute Stance Formula: 0.4*HP Heals this Champion by 40% of their MAX HP and places a [Counterattack] buff on this Champion for 2 turns. Cooldown: 4 Counterattack	Hypnotize Formula: 4.7DEF Formula: 0.5MAX_STAMINA Attacks 1 enemy. Decreases the target's Turn Meter by 50%. If the target's Turn Meter is fully depleted, places a [Sleep] debuff on them for 1 turn. Cooldown: 5 Sleep	-