After you play a match, in addition to the current cbill and xp/gxp earnings, you get a “token”. You get one token for a loss, two for a win and they are banked in the front end just like cbills, mc, xp, and gxp.
While in the front end, you can spend your tokens for grab bag items, one token per chance. Rewards from these grab bag chances include cbills or various equipment for mechs. No MC or MC items and no engines, endo, ferro, artemis. Only cbill items less than 1 million cbills.
There should be no way outside of match results to obtain tokens, and no way to “better” your chances at the grab bag.
“Oh no, not another currency!” Hey, Star Trek Online would like a word with you…
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For lore purposes, there are many currencies to choose from if you want to. Each house and each periphery state has its own currency as well as Comstar (cbill).