Their prohibitive costs make most mercenary ships a gamble, particularly since they don't upgrade throughout the game and their specific natures all but broadcast your victory strategy to your opponents. That sometimes meant I didn't need them at all when my strategy was unfolding well, and the AI would seem to agree, as it uses mercenaries sparingly at best.

Mercenaries are best used to make a massive leap in progress (and they thus sometimes only serve to make the powerful more powerful) or to gain a significant advantage when in a tight spot. Nus will flutter about the unfriendly nebulae. Though whatever I buy stays mine for the duration of the match, so there's no worry that multiple Ms. But it's a controlled chaos, at least, held in check partly by the fact that each faction has access to the same catalog of mercs, which randomly selects an assortment of 36 for each match from a total pool of 70. Nu's can disrupt a match so thoroughly I'm surprised there's no way to disable the Bazaar in custom matches.

Overpowered? Almost certainly, and ships like Ms.

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