Frontline is a large-scale, 3-way battle for domination. The battles generally feature a large open area where three teams of up to 24 players each compete for control of a vast wasteland with allagan technology lying about. There are four modes across three different areas, the Carteneau Flats (CF), Seal Rock (SR) or the Fields of Glory (FoG).
- "Secure" (CF), where the goal is to be the first team to accumulate a set Tactical Rating score, which is earned from taking control points, defeating opponents, and killing special monsters. Added in Patch 2.3
- "Seize" (SR), where teams compete to obtain valuable data from Allagan tomeliths which appear around the area. Added in Patch 3.05
- "Shatter" (FoG), which is a bit of a hybrid of the other modes, where the goal is to earn points through controlling capture points like Secure, kills as in Slaughter, and by destroying Icebound Tomeliths.
- A random frontline battle can be accessed via the Duty Roulette.
Frontline also contains unique battle mechanics such as "battle highs" which reward kill streaks and unique game objectives for each mode.
Regardless of area and mode, Frontline is made to be accessible to all and has minimal requirements in order to facilitate party matching- players may even change jobs in their team's starting area.