Garry's Mod

Garry's Mod is a game where you can make anything you want. For example you can make guns, robots, cars, ships, planes, some random thing that can fly, ect. You can use hover balls to make objects float up and down with a key you choose. You can weld objects together to make things our towers and such. You can use thrusters to make a jet pack our a plane to.

So there are infinite things you can do, you can even make your own game mode for players to play. There are game modes like trouble in terrorist town were you have to find the traitor terrorist before he kills all the other terrorists.

There tons of other game modes to play so its always fun to play Garry's mod. Garry's Mod use's other games for items such as half life so some items you cant get do to them being in games you need to have. So trouble in terrorist town needs to have counter strike items to play our your gonna have error signs everywhere.
Buy the game $9.99 or $24.99 for Garry's mod and counter strike together.

Awesomenauts

In this game you objective is to destroy the enemies drill. To do this you need to fight through the other teams and destroy their turret. The enemies base will send endless small creeps that you can kill for money and use to buy upgrades for your guy. Each character has different abilities that can be used. The great thing about it is each character has unique attacks and skills so you can never be bored.

Lots of new characters are being made for the game so you never run out. You can buy this on steam for pretty cheap its Mac and Pc, its not to much money and most computers can handle it. You can also buy skins to use for all the characters if you want to look different from everyone else :)

Roller Coaster Tycoon 3

Roller Coaster Tycoon 3 is a tycoon where you can make your own park. They have different extra packs you can get like making a pool our zoo. You can make your own, custom roller coaster our get a one made for you. If you want to make your dream park you can go into sandbox mode were you get infinite money and tons of people coming into your park even if you dont have anything. When your making your roller coasters you need to test. There is 3 things you need to get in a range to get more people on your coaster. 1 nausea, if its to high most people wont go on the ride. 2 intensity, same  thing, cant have it to high. 3 excitement, Try to get this high so people want to go on your roller coaster.

 There our tons of cheats in roller coaster tycoon, to do some click on a person in your park and you can retype their name. A funny cheat is were you can ride a dune buggy in your park to do this change the name of a person to "James Hunt" and click on the buggy.