Troop HP: increase
Troop DEF: increase
Troop ATK: increase
Mars is one of the top heroes for sure. At higher enhancements his damage is insane. Chaotic Surge depletes 25% of a target’s Rage and his other two skills are designed to enhance your allies during attack. Tactical Drift at +0 hits for 440 damage by itself.
If that doesn’t pique your interest he is another hero whose troop skills all increase overall troop bonuses. He should definitely be upgraded to 131.