Recs.
Updated
Team Fortress 2 is a multi-platform, team-based, first-person shooter, multiplayer video game.
SpecsUpdate
Pros
Pro Includes Mann vs. Machine, a ridiculously fun co-op mode
Mann vs. Machine is a co-op mode in Team Fortress 2 that is comprised of gameplay in which 6 players team up to stop AI robots from deploying a bomb. Though not the central gameplay of Team Fortress 2, it is a mode that allows for co-op play to be enjoyed with the characters of the game.
Mann vs machine works quite well over LAN and is very fun to boot.
Pro Good VR support
To enable VR support, type -vr in console.
TF2 has 8 modes in which to control the game. They can be changed with the command vr_moveaim_mode in console. They offer choice in what combination of aiming and steering should be coupled to the rift and mouse and introduce the concept of dead zones - an area of the screen that controls differently when aiming or steering within its bounds than outside them.
Typing vr_calibration in console gives access to adjusting interpupillary distance (distance between eyes). You can get that information from an optician or use the calibration tool to help figure it out and set it there.
Calibration will help set accurate render point (camera position) and reduce nausea.
Pro Multiple game modes allowing for great variation
TF2 has more than 10 game modes, plus variations on those, as well as community mods that offer a wide range of objective-based play. Classic game modes include Capture the Flag, Control Point, King of the Hill and Payload. There's also Mann vs. Machine, a co-operative game mode where you play against waves of AI controlled enemies.
Cons
Con Free accounts are slightly limited
Free accounts do not get rare and cosmetic items nor as many storage slots for items.
Items are relevant as free accounts can only hold 50, while the game has much more than 50 pieces of equipment (that affect gameplay), let alone 50 weapons. While a premium account player can react to almost all situations with a counter item, with only 50 slots a newbie probably won't have or even be able to access it. A full inventory also means a free player will have to miss out or delete exclusive event items and cosmetics just to play the game as full as they can.
A free account is upgraded when any item is purchased with real money from the store.