Here's my long and convoluted post on every unlockable weapon:
Scout:
Force-A-Nature: I used to like it, but after switching back to the scattergun, you learn how much those 4 other rounds really helped. It has it's useful situations, but most of the time it seems you'll get killed before you kill someone with it
Bonk!: Good against sentries. Not much else use. Usually I'll see people use it, and run around in front of me until it wears off. Then I kill them.
Crit-a-cola: Worthless.
I've been using it since I crafted it to see if it could get better, but it can't. The fact that YOU take mini crits as well as give them really only makes it useful when your enemy doesn't have much health left.
Sandman: Since it has been nerfed so much, it's not so great. Not much more to say about that.
Soldier:
Direct Hit: Same as sandman. The rage meter doesn't fill fast enough, since they lowered the value, so if you're using the buff banner, you should use the rocket launcher. It has it's situations, though. I like it for defense on payload maps when everyone is around the cart. It's a nice target to aim at.
Buff Banner: I love it. I haven't missed my shotgun once.
Gunboats: Haven't really found a good situation to use it over the buff banner or shotgun, but it does its job.
Equalizer: Haven't gone back to the shovel since I got it. Since you're usually pretty hurt when you're trying to melee someone (I mean, you're out of ammo. You're probably gonna be hurt) it's a nice way to finish someone off. The extra speed is fantastic too.
Pain Train: I like to use it when I'm playing soldier or demo on CP maps.
Pyro:
Backburner: As with the sandman and direct hit, it's been nerfed too much for me to like it so much anymore. I used to use it all the time, but I've switched back to the flamethrower. I still like it on 2fort, however.
Flare gun: More of an annoyance than a weapon. I don't feel it's effective enough to do much.
Axtinguisher: Been using it since I got it. Great unlock
Homewecker: If you're gonna be an engy farm guard, by all means, use it. Help em get those sappers off. Otherwise? I don't see it worth much. If you're close enough to melee a building, you're close enough to burn it.
Demoman:
Chargin' Targe: Used to use it, but I missed my stickies too much. Not much else to say. Oh, yes there is. I miss being able to catch up to people easily.
Scottish Resistance: If I use it, I use it on defense so I can guard a few areas at once.
Eyelander: Favorite demo melee weapon. Great all around.
Pain train: See soldier
Scotsman's Skullcutter: It has some nice abilities, but I can't deal with the slower movement speed. The demoman needs to be fast. Maybe a good combination with the Chargin Targe.
Heavy:
Natascha: Good sidegrade. It's pretty equal to the minigun since you'll be hitting them more even though it does less damage. Also, it sounds better.
Sandvich: Great for when you don't have a medic
Dalokoh's Bar: Awful. If you have a medic, it's effects don't matter. You don't get healed to 500 health as I learned yesterday. Don't see much of a point to use it instead of the sandvich
KGB: Fantastic. You might not get a kill, but if you do, and there's other people around...
Engineer:
OH WAIT
Medic:
Blutsauger: Until recently, I only used it. Then I remembered about the regeneration being lowered with it out, and tried the syringe gun again. The 3-6 hp/s regeneration instead of the 1-4 hp/s is great. And unlike the blutsauger, it's ALWAYS higher, not just when you're shooting someone with it. Also, crits!
Kritzkreig: Always use on defense. Always use medigun on offence.
Ubersaw: Haven't looked back. Getting +25% uber is totally worth the slower speed
Sniper:
Huntsman: If you want to get up close and personal, use it. Great combo w/ jarate. Can't say much else.
Jarate: I always use it with the huntsman
Razorback: I always use it with the sniper rifle
Tribalman's Shiv: The reduced damage is made up with the bleeding. Why wouldn't you use it?
Spy:
Ambassador: I've been using it, but I think I'm gonna switch back. I only really use it when I need to GTFO, and I don't have the time to aim perfectly for the head of my enemy
Cloak and Dagger: Love it for payload maps. I sit off somewhere where nobody can see me, invisible, and just wait for the perfect moment.
Also, to respond to Lyriq, standing still is GREAT for a spy. That's NOT what people expect. If my cloak runs out temporarily, if I just stand somewhere, I'll most likely survive instead of running off, since the person chasing me has a good idea of where people would usually run as a spy.
Dead ringer: Don't really like it. You might get a couple stabs, but as soon as the team is aware you have a dead ringer spy, you become dead. A lot. (Well, as long as the enemy isn't stupid.
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