Vanguard
Vanguards use Max HP to absorb and dish out damage.
Vanguard Mechanics: Rush, Shields, Burn.
Vanguard Heroes
A and S rank upgrades are class upgrades: the options come from the hero's class, not the hero (game tutorial). In the current data the A and S rank options are the same list.
A/S rank options 15

At start of combat, give this Hero and adjacent Heroes (+25% Max HP) Max HP.

The first time each combat this Hero goes below 50% Max HP, they gain (+50% Max HP) Shields and deal (+50% Max HP) damage to adjacent enemies.

Vanguards gain 13 (+10 per rank) HP/S. Backup.

After Stall (10, 20, 30, 40, and 50): Taunt all enemies.

Each second, deal (+3% Max HP) damage to adjacent enemies.

On Rush trigger, gain 100 Max HP, 12 Attack, and 10 Attack Speed.

For Rush (12), gain +100% Max HP.

Rush abilities last 3 seconds longer. Backup.

On auto attack or when auto attacked, inflict 1 (+1 per 800 Max HP) Burn on the enemy (Max: 7).

Vanguards gain 50 (+50 per rank) Attack. Backup.

At start of combat, inflict 30 (+1 per 50 Max HP) Burn on all enemies.

On auto attack or when auto attacked, if the enemy has Burn gain 1 HP/S.

Whenever a Vanguard auto attacks or is auto attacked, they gain 25 Shields. Backup.

Gain 1000 Max HP and 20 Omnivamp.

At start of combat, give all Heroes in the front 2 rows (+66% Max HP) Shields.
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