Halo 4- 7D 13H 38M
Halo: Reach- 15D 00H 36M
Halo 3- 11D 2H 13M (multiplayer only)
I've put more time into Halo 3 than either Reach or 4 if single player is included, plus I didn't get XBL until 3 months after Halo 3 released so all together probably 17-19Ds for Halo 3.
No way to tell how much time I put into Halo:CE and Halo 2, except that it was a lot. Halo Wars roughly 2 days.











