Door Kickers PC

Great game to pass the time.
Starts off easy and builds up into more complex missions. Plenty of videos with tips online if you search.
Offers something a little different to usual shooter/top down shooter.
Customisable loadouts so you can try different tactics.
Quite a lot of campaign missions to play through, even more single missions to do and there is a random mission generator and you can download more missions via the game.
Well worth buying for a couple of quid.