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Commander is a rank among the Cabal Military, serving as a possible superior to Val.
Commanders are often Centurions, like most Cabal leaders. Though not explicitly confirmed or mentioned, Commander Truvul is seen leading two Vals - the equivalent of a captain - in a raid against the Warmind Rasputin, suggesting it is a higher rank.
There is also one Cabal known to possess the rank Field Commander as seen with Field Commander Kuskan, Forge Saboteur.
List of appearances