A game that was never planned, and will never exist. Only idiots actually believe it will become a reality.
Joe: OMG! Halo 2.5 is gonna come on the hard drive of the Xbox 360!!! Like, my uncle who works for Bungie told me!!!11!1!!!oneone!!!1

Bob: You are a total retard.
by dabears1020 October 14, 2005
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that one thing they say will come out for xbox 2. it better not suck as much as 2.
halo 2 that is.
its halo 2.5 wtf do i need an example?!
by I March 30, 2005
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The game being released by bungie, an updated version with a better ending than the Halo 2 crappy one.
1."Halo 2's ending both sucked and blowed"

2. "Yeah but they are releasing Halo 2.5 with a better ending"

3. "Shutup! Smart ass!"
by Halo master August 16, 2005
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