Before I buy, curious on one trick ponying in this game...

[Soulwind]

Promise last question...

How about Mercy for a one trick champion? Now, I read what everything people said but you know why this just came to mind? Healers ALWAYS FIT INTO EVERYTHING in competitive games. I don't like to talk of it due to distaste for the champion nowadays but I admit I played Soraka (League's go-to and only real healer) to about Diamond IV last season. Another example is how I think of how invaluable the Medic is in TF2 and has the largest bearing in competitive play for that game, being in every team no question.

She's great, as long as there aren't any other support heroes.

Unlike Zenyatta, Symmetra and Lucio, Mercy does no damage (she has a pea-shooter but you shouldn't use it). If someone else is already playing a support, you shouldn't be Mercy or else your group will lack damage.

You don't want to be a constant your teammates have to work around. You are supposed to help them, not become as much of an obstacle as the enemy composition or the map. Be adaptable and helpful and you will not only win more, but also get more chances to play your favourite hero.

She is but Winston is better at that role in my opinion. She's more fun to play though and she can get the job done pretty well.

It depends on the map. Winston's jump can be a bit unreliable compared to D.Va's flight, and you risk getting stuck and killed trying to fit through a hole or something like that. He is tankier, and his ult makes him pretty much unkillable. I find him great at stalling, like Mei.

[Tojara]

I don't think Reaper is universally sound in all situations, still quite good though.

If you want to play exclusively one hero without hampering your team, the best ones to play are probably Tracer, Lucio and McCree at the moment. I can't think of a situation currently, albeit incredibly rare ones where any of these heroes are bad.

I'd still advice getting good at at least 2-3 heroes though at minimum.

She's great, as long as there aren't any other support heroes.

Unlike Zenyatta, Symmetra and Lucio, Mercy does no damage (she has a pea-shooter but you shouldn't use it). If someone else is already playing a support, you shouldn't be Mercy or else your group will lack damage.

You don't want to be a constant in this game your teammates have to work around. You are supposed to help them, not become as much of an obstacle as the enemy composition or the map. Be adaptable and helpful and you will not only win more, but also get more chances to play your favourite hero.

Mercy does fine damage and it's not great advice to never use her pistol at all. There are plenty of situations where if you have good aim that its perfectly viable, and the right call to actually her weapon. It does decent damage, is pretty easy to aim with, and for all intent and purpose is a slightly slower traveling weapon that D'va has when not in her mech. Keep in mind you shouldn't be using it all the time, but good Mercy's shouldn't completely forgo using it.

Mercy with Lucio is pretty popular too, no reason you can't double up on supports in some situations.

[Soulwind]

I don't think Reaper is universally sound in all situations, still quite good though.

If you want to play exclusively one hero without hampering your team, the best ones to play are probably Tracer, Lucio and McCree at the moment. I can't think of a situation currently, albeit incredibly rare ones where any of these heroes are bad.

I'd still advice getting good at at least 2-3 heroes though at minimum.

I can think of one: The team already having a Tracer, Lucio or McCree. None of them work well in pairs.

Mercy does fine damage and it's not great advice to never use her pistol at all. There are plenty of situations where if you have good aim that its perfectly viable, and the right call to actually her weapon. It does decent damage, is pretty easy to aim with, and for all intent and purpose is a slightly slower traveling weapon that D'va has when not in her mech. Keep in mind you shouldn't be using it all the time, but good Mercy's shouldn't completely forgo using it.

Mercy with Lucio is pretty popular too, no reason you can't double up on supports in some situations.

He's asking for basic information and a hero that "always works", obviously my answer was simplistic, but it's generally not a good idea to have a Mercy with another support, which means she's not what he's looking for. Every hero can work with every hero in some situations. That's kind of the point of the game.

As for the gun, it's very situational, and using it means not healing or boosting someone else. She's definitely nowhere near as powerful as the other supports with that, which is why I highlight the lack of team damage as a reason not to pick her -always-.

[Tojara]

I can think of one: The team already having a Tracer, Lucio or McCree. None of them work well in pairs.

That's also not true. You can and should double up on heroes in some situations as well.

Double Lucio is popular as well.

[Very Tired]

Don't listen to all the people crying for swapping. That's just the new flavor of the month excuse for why their team sucks and they lost. MMR in the game is nonexistent, it's rare you'll actually find a fairly matched fight. So you should be prepared to be stomped, or be the one doing the stomping, swapping heroes isn't really going to change that. The better team will always win.

[Soulwind]

That's also not true. You can and should double up on heroes in some situations as well.

Double Lucio is popular as well.

And again the key words are "some situations". The OP is looking for a hero that works in "all situations", and that doesn't exist.

Don't listen to all the people crying for swapping. That's just the new flavor of the month excuse for why their team sucks and they lost. MMR in the game is nonexistent, it's rare you'll actually find a fairly matched fight. So you should be prepared to be stomped, or be the one doing the stomping, swapping heroes isn't really going to change that. The better team will always win.

I've already seen tons of games where switching heroes has made all the difference. In fact, I'd say the difference in skill must be huge for switching not to completely turn the match around. Which eventually will be the minority of the games.

[Skylarking]

The better team will always win.

To a certain extent thats true yes (in pub play), but swapping to a better suited hero can still clutch the victory for your team.

[Endus]

I've already seen tons of games where switching heroes has made all the difference. In fact, I'd say the difference in skill must be huge for switching not to completely turn the match around. Which eventually will be the minority of the games.

Yep, had a game last night where we got hammered on defense and pushed to the final point. I swapped to Zarya (had been playing Reinhardt), because they were mostly poking at us from range, and some of my teammates swapped to better heroes for the mix, and we held the final point until victory.

Sure, you get big skill differentials as the matchmaking is still building up info, but pretending that swapping is pointless is just untrue. I'd venture that attitude is why people see matches as inevitable once they start losing. Their opponents had a better composition, and they didn't adjust to counter it, so of course it became a steamroll.

[Aeiri]

You need to find a balance. After skimming through this thread there are people shouting about how the only way to play the game is to know how to play everything, and a rarer few saying it wont matter. It's somewhere in between.

I'd highly suggest playing everything and narrow it down to 3-4 heroes you really feel like you click with playstyle wise and run with them. You will never be as good at the game if you try to master everything, but at the same time the hero swapping is a big enough point that if you play one hero only, even if you are god tier with him you are going to run into the issue of being hard countered by a slightly less skilled person and it not mattering.

If you have a smaller hero pool then you still have the ability to swap but you aren't screwing yourself. Not everyone is a sponsored progamer who can devote 8+ hours of practice a day to master all the heroes otherwise that would be the route to go. If you're a normal person with a job that loves playing competitively in your spare time, stick to 3-4.