If you could make your own COD game

If you could make your [COD] game what would you do

I would do this

Wars-Revolutionary war US-Civil War World War One and a war that take place on mars in like the 2100s[NOTE:HUMAN VS HUMAN NO ALIANS IN MARS 2100 IN MULTIPLAYER AND CAMPAIGN]

Score streaks-world war one zeppelin gunship and a zeppelin bomber and instead of a nuke poison gas

Campaign-[Civil war]a halo 2 style game play were you play some levels a a union soldier and some levels as a confederate soldier

Zombies-MARS 2100[Aliens apply here] they find Alien text and tech on mars that can bring back the dead