Halo 3 was the last game within the original halo trilogy, halo reach was the last game within the halo series however it is rumoured that a different games producer is working on a secret halo project that many know to be called halo the marine, but it is not official.
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It has been confirmed by 343 studios that there will be a halo 4. It will be the first halo game to not be created by Bungie.
Halo 4 is called Halo 4.
Halo rights are owned by Bungee. Technically Halo 4 is "Halo ODST"
Yes, there is a Halo 4.
There is multiplayer in halo 4
there is no halo 4 because it is a trilogy. halo 3 was the end of the series.
halo 4 limited edition, comes with a copy of halo 4, a T-shirt and special armor customization.
Masterchief
No, the Arbiter is not in Halo 4.
Halo 4
In the Halo Universe, Halo CE. In reality, Halo 4.
Not yet, but there will be. Well, technically, you could classify Halo: Reach as Halo 4, but as for the actual Halo 4, its currently in development by 343 Industries.
Halo 5 will most likely follow the story line of Halo 3/Halo 4.