Halo seems to be on repeat kinda.

Halo CE: Great campaign with a not great multiplayer
Halo 2: lackluster campaign with amazing multiplayer
Halo 3: great campaign with amazing multiplayer

Halo 4: good campaign with not so great multiplayer
Halo 5: lackluster campaign with good multiplayer (it has issues, but is better than 4's)
Halo 6: hopefully great campaign and amazing multiplayer