Ranks are a mechanic akin to levelling up the pilot's mech. At the end of every match, regardless of gamemode, the mechs that were used by the pilot receive XP proportionally to the time they spent ingame and their performance while in use (so for example, a mech that was used only a few minutes will receive less XP than a mech that was used for twenty minutes).
Mechs start at rank 1, and for every subsequent rank they unlock by gaining XP, they unlock special Elite mech parts specific to the mech type, paint patterns, or alternate primary weapons. This goes on to rank 6. All XP gained after reaching rank 6 is transferred to an XP pool, where it can be transferred to other mechs if they are under rank 6 for an MC fee.
Unlocked Elite Mech Parts and paint patterns can be equipped to the ranked up mech for free, but are not transferrable to other mechs. Unlocked alternate primary weapons cost an additional 4130 HC or 512 MC. The weapons can also be unlocked without ranking up by paying an additional MC fee.