Doom Eternal is a constant barrage of fun. It takes what Doom 2016 did to innovate FPS games to the next level. The focus is on the gameplay, first and foremost. Levels are better designed than they ever were in 2016, with lots more open environments and movement. Doomguy has more movement options in this game than he did in 2016, and the levels are definitely built to take advantage of that. The guns are all great, and I think that I regularly used just about all of them in every level. The combat is now even more tied to the movement-- If you don't move fast, you will die on higher difficulties.
The story is also more prominent in this game than it was in 2016, and it is GOOD! Just like 2016, there is a codex that you build up as you play with plenty of lore, but the game also has a larger number of cutscenes (skippable) as well.
Overall, Doom Eternal was a blast to play and the campaign alone is worth $60. (Also they removed Denuvo in May 2020, ignore any negative reviews you see talking about it).

If you can get put aside the fact of DRM on this game, it is absolutely worth every penny. I haven't played it in weeks because I've been busy, but I still think about it at least every other day. The game is absolutely phenominal and is the greatest love letter to the Sonic franchise ever made. This is what Generations should have been. Everything is phenominal: The art, the music, the level design, and the gameplay. These people know what makes a good Sonic game. I'd put it up there with Sonic 3 (Complete) as my favorite Sonic game ever made. I can't wait to do another playthrough of the game!
It's a shame Sega of Europe forced this DRM on the game, but I haven't seen a performance hit on my computer (granted, my computer is pretty beefy with an i5-6600k and GTX 1060 6GB). The DRM was pointless in the end, because not only does it not do what it claims (prevent modification of game files), but it was cracked within a week.
I would recommend this game to anyone who has ever played and enjoyed a 2D platformer.

Garry's Mod is a very different game. If you want to just fool around in the maps of Half-Life 2 or pose ragdolls around in the maps of Team Fortress 2, then you'll love it! If you want to play some of the best multiplayer minigames, then this game is for you.

This game is great! If you like Indie games, 2D Platformers, extremely challenging games, controllers, and Meat, then this game is for you!
As I stated, the game is quite challenging, but in such a way that it is very fun. I'm not sure that it's worth the $15 price tag, as I paid about $4 for it during the Summer Sale. At that price, it is definitely worth it.

I originally wrote a glowing (and very of-the-time) review of this game back in 2013, but I can no longer recommend it. This game has become much more difficult to play as its servers have been taken over by malicious cheating bots. It's gotten to the point now where players have to take a break from the action very frequently in order to votekick the bots.

Original review below:
Team Fortress is definitely a great game. It's different from other FPS's in the way that all of the classes have their own crazy personalities and quirks. There's also... hats... hats... HATS! Yeah hats are insanely popular in TF2, but you have to become a premium member to recieve them as a drop, to trade for items, and to be able to craft rare items such as hats. It is Free-to-Play, meaning you don't HAVE to pay, but if you enjoy it after being Free-to-Play, consider buying something from the Mann Co. store ingame to become premium.