Possibly best online FPS ever made!
Like I said, TEAM WORK. You can be the best TF2 player in the world but if the rest of you're team sucks then your skills will matter not.
You get to choose which one of the nine classes you want to play either at the start of the map or in you're team base. You can change anytime but your class will suicide if not in the base. Every class is unique.
Every class has their own distinctive appearance and personality. You'll find yourself sometimes spamming the voice commands just to hear every classes own take on "medic!" "positive" "spy!" and many more commands! Also sometimes the classes talk to each other without even the players intention, like when a medic heals you and your class thanks the medic, or when you dominate an opposing player and your class bawls into hysterical laughter. These are only two examples, and the idea is to make you feel like you're apart of something, and useful to your team.
Onto tactics every class has their strengths and weaknesses which are all counteracted by the other classes. A bit like paper, rock, scissors. Example,
the demo is very powerful with explosives, he can detonate his stickies at any time he wants, but on an open battlefield something as weak as the scout (fast but tiny health) kicks the crap out of him. The demo just cannot keep up with the speed and randomness of an experienced scout. Another example is the heavy. His strength is that his weapon is by far the most fastest automated gun in the game, meaning he hits what he aims for with no delay. His weakness is his shots don't count for much at far distances (but still injure) and in this situation he's vulnerable to all explosive classes. A heavy has the most life of all classes in the game but it doesn't count for much unless he has a medic. The biggest problem for a heavy-medic combo is the far away haven sniper, or, backstabbing spies and pyros up your ass. Howerver if the heavy and medic work well together, using movement communication, both will remain alive and reak havoc on pretty much anything in sight.
I could spend all day explaining scenarios and useful class combos but when you're in game you just gotta decide which is best tactic/combo to use in the right situation. And like I said before, it requires TEAM WORK. If you're team are idiots and choose the wrong classes in the wrong situation it won't matter how skilled you are, you will lose. So everyone needs to do their part.
Bad things about the game. Tf2 can seem like a crap game if you're team isn't trying. All classes are simple and weak by themselves and if you don't use team work the game can feel pretty fustrating. In times like these, it's easy to see why some people wrongly feel the game has no substance and has been rushed by game developers. Many reviewers, but not all, join crap servers and write their reviews based purely on their bad team experience. To those reviewers I would suggest finding a good server with a good team play and perhaps rejudging or reviewing the game again.
You will find TF2 probably requires more tactics and team sync than most other games out there. The amount of scenarios which can be played out is daunting. I've played for more than 100 hours and everyday I see different ways of playing out a map.
Another hate of mine is TF2 is the new medic weapons. IMO this goes against everything the old TF2 stood for. On some servers the whole unique point of the medic has completely gone out of window. Especially with the new melee and needle gun weapons. IMO medics should always be healing rather than attacking; except when they need to.
One of the achievements to unlock weapons is... "bonesaw 50 scouts"
A medic should never be taking on scouts, let alone 50 of them.
Thankfully since the update most medics have gone back to their healing jobs but you still see some combat medics not healing at all.
Anyway despite those bad stuff I give the game 10/10 cause it's probably my all time favourite game ever. I recommend everyone that likes to be a part of the team to play this, and it caters to almost everyone that has played an online fps before. From the old sniper vet to the camping aimbot like engineer, lol.