Terminator

[Relic]

Mod for factorio allowing players to construct Bug Fighting Terminator like robots?

[Overeagerdragon]

already present....AAI let's you turn your game into a Command and Conquer/starcraft type of game, Necromant turns it into a "Evil pokemon" type of game and I think Yuoki has the option to build remote operated "clones" which you can send at your enemies.

I remember there's a robot mod as well which allows you to build avatars to combat your enemies. If you want to turn Factorio into an RTS; there's plenty of mods that allow you to do that.

[Relic]

What would be your recommendation for something simple with just afew features? All i really want is a basic like unmanned robots that i can have protect or attack locations.

[Fel]

If you don't need to automate the vehicles then you can go with the basic package:
https://mods.factorio.com/mod/aai-signals (hard requirement for the main AAI mod)
https://mods.factorio.com/mod/aai-programmable-vehicles (main AAI mod)

If you also want extra vehicles, there are a decent amount:
https://mods.factorio.com/mod/aai-vehicles-warden (a support vehicle that can repair)
https://mods.factorio.com/mod/aai-vehicles-chaingunner (very basic "turret that can move")
https://mods.factorio.com/mod/aai-vehicles-laser-tank (a tank that uses laser as weapon, slow fire rate but high damage and even capable of AoE in a line with the right ammo)
https://mods.factorio.com/mod/aai-vehicles-flame-tumbler (a very quick car that can ram pretty well and has a flamethrower)
https://mods.factorio.com/mod/aai-vehicles-flame-tank (removes the flamethrower from the vanilla tank and puts it in this vehicle instead, making it into a durable front line unit)

[Kai]

Is it possible to use AAI in PVP so it's more interesting to have robot/clone armies to fight one another, but not completely fly over everything.

A 'MOBA' style PVP with two AI factions sending units at each other while human players build outposts and try to flank each other and steal resources.

[Fel]

If the path is simple enough it should be possible to cook up something like.
You will need the two more advanced parts of the AAI mod:
https://mods.factorio.com/mod/aai-programmable-structures
https://mods.factorio.com/mod/aai-zones

With those two you can automate the deployment and orders.
You would most likely need house rules in order to not have players just take a vehicle for themselves and just barge in early and such.

(I'm also not sure how such a PvP game would work all that well because it is just torturing an existing game concept to try to make it somewhat work in a game with completely different rules and systems, but that's not up to me)