Step one: design concept

Step two: choose setting

Step three: Write the script

Step four: Scrap the project

Step five: Partner with SE to make a sequel to Chrono Trigger/Cross instead

Campaign: Aliens land in the world war 1 era and destroy the allied and the central powers, the place they land is hence called no man's land. The player/Taylor from Black Ops 3 time travels back in time to WW1 and has an hour to kill all aliens before his mech suit runs out of battery, he fails but instead brings the aliens to the future timeline so as to be better equipped to fight them, a huge war occurs filled with space battles, ground battles, water battles. You can slide on water at high speeds and monsters come out of the water, there are platforms that you can wall run around the monster and shoot while dodging its beams and making sure you jump onto the right platform. In the end, the aliens are actually heavily mutated intelligent humans from a parallel universe that wanted to take refuge in this universe since there was a large unseen threat named GOD destroying planets in their universe. You make a treaty with the humans and deport them to Mars and they make a colony out of it. 100 years pass and nothing happens, the humans "interbreed" and thanks to natural selection mutant kids are being born, life is good. Mars is a whole civilization, humans finally colonize 2 whole planets to themselves. I'm done now, idgaf just like the COD campaign writers.

Multiplayer: 100 player servers. Winner is determined by going through a portal which is hidden in the map somewhere could be in the mountains, in the river, in the sky, anywhere. There are certain items/ special telescopes that lead you towards the secret portal but is only shown once during the whole match and there's no minimap. The map also has dangerous wildlife and trees that emit poisonous gas. Kill a boss and it can lead you to the portal but it calls attention to other players and they can reach first.

Hire me Treyarch!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

A COD rhythm game with kinect support and loot boxes.

Call of Duty: The American Revolution. You use a muzzle-loading musket that has to be reloaded after each shot by using the controller buttons to load the powder, wadding, and shot in the correct order. Competitive death match modes included.