Garry's Mod to me is a game where you are able to create anything you want with no limits! Think of Minecraft, but non-blocky. Garry's Mod let's you download/subscribe to different workshop submissions and let's you use them in game for customization, player models, monsters, more ragdolls, and way more! This game is also pretty good for starting animation videos. I guarantee you will like this game and what you are able to do in it.