The Siege Mech constantly seeks for targets as it walks. Once it has found a target (a hero or defense), the mech will fire volleys of rockets at it. At melee range, it'll use its flamethrower instead. Both attacks hit multiple times, summing up to a lot of damage. When destroyed, the mech releases a fiery explosion as it collapses. This inflicts high fire damage to anything around it.
The mech's aggro behavior is similar to that of ogres. They'll target heroes and physical defenses who damaged them and change targets if someone or something else deals more DPS to it. While aggroed, mechs do not acknowledge other player-made obstacles in their way.
Siege Mechs cannot damage Eternia Crystals.
- Reflection Beams can send back the mech's rockets, as well as block its flamethrower.
- Each Siege Mech destroyed gives a "Boss Slayer" award, despite the fact this enemy is not announced on arrival and isn't an actual boss. On Nightmare Hardcore, every mech defeated effectively yields 47,000 experience points.