It either means these things:
-A brave soldier in the military.
-An edgy kid that commands other edgy kids to raid someone's discord server for no good reason, thinking he's a military leader of an army of edgelords.
-Another word for tank and/or soldier.
Kid: When I grow up, I want to be a warstar!

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Edgelord A: Raid this dude's discord server because I don't like him!
(*Army of edgelords raids Dude's discord server*)

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Soldier A: When I saw the warstar, I was surprised by it's massive size!

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Fan A: That warstar in the show was very fucking big in comparison to the other warstars in the show!
Fan B: I know, right?
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