- Seen in: “The First Step”
- Previous: Battle of Ceres
- Next: Third Battle of Venus
- War: Neosapien War
- Year: 2120
- Location: Mercury
- Tactical victory: Exofleet, Pirate Clans
- Strategic victory: Exofleet, Pirate Clans
- Pirate Clans
- Neosapien Commonwealth
- Exofleet: E-frames, jumptroops
- Pirate Clans:
- Neosapien Commonwealth: Mercury Outpost, E-frames, Neosapien Hovertanks
The capture of Mercury would provide a forward operating base for the attack on Venus. The jumptroops would assault the outpost while the E-frames would provide air support.
Upon reaching Mercury Exofleet engaged in combat with the Neosapien E-frame contingent that was stationed on Mercury. Soon after Marsh ordered a recall since the jumptroops were being sent in for the ground assault. Once they landed the jumptroops headed for the outpost.
After landing at the outpost, Thrax and Glycon discussed the fact that no reinforcements would be sent. Glycon stated that he would lead a counterattack against the jumptroops, which would draw in the Exofleet E-frames. Thrax would then attack the Wellington in orbit.
Soon after the counterattack began, Butler called for air support since he was facing hovertanks. Glycon ordered Thrax to attack the Wellington and soon after the Neosapien ground counterattack was destroyed. Marsh ordered the E-frames to return to the Wellington after receiving a distress call. The return of the E-frames broke the space counterattack and the Neosapien survivors fled to Venus.