For months now this person on the team has been extremely competitive and passive-agressive. They would interupt other people and step over a discussion to prove they're the loudest voice. Sometimes going to the extreme of claiming others work as their own just to come on top. Gets even worse when high-chain personnel are in the room, any other team member would be lucky if they get a chance to speak or show their contribution. Have you ever encountered someone like this? How do you deal with it?
Management understands such a holes are ambitious and will get things done. As long as things don’t become toxic this persons will be promoted.
But it always end up choosing one side, and the show pony always wins
Nope. A good manager will resolve this. If you don't bring this up thinking that "show pony always wins", it is mostly your fault if the situation is not rectified. How do you expect an issue to get fixed if you don't bring it up? It's like expecting a broken taillight on your car to fix itself, or hoping that a mechanic walks by while you are sleeping at home and fixed the light without you bringing it up. You have to take the car to a shop and point out the issues. Then the expert mechanic will fix it.
It happens a lot, you have two choices. Make yourself heard and challenge their position strongly but politely during the discussion. They generally back down. Also do prep meetings with individual stakeholders beforehand so you can peacefully make your case. Other choice is just find another team/company which has more peaceful conducive team. This depends a lot on manager too. If the manager is involved in teams work and knows the nitty gritty of everyones work, the vocal one doesn't get much heed. But if manager is hands off then they love that vocal guy just trusting their confidence.
How can he claim others work? Don't you have git history or review history? I use emails to mailing list in case something needs discussions or we have already discussed with conclusion so that we have a history of what happened. Don't leave anything undocumented.
I don’t think he really meant work but ideas. You generally discuss ideas with your team mates without documenting.
Can he really back up the work he claims? The taller they make themselves the harder they fall and a noisy wagon is an empty one. I think he may be his own downfall but I know it is hard to deal with in the mean time. Document everything, build your own strong relationships in the company. You will have people to back you up when you are ready to bring this forward.
I have been through this exact situation and my suggestion would be to change the team or company. It is wastage of time to try to change that person. BTW this person you are describing is not competitive in a positive manner but trying his best to be politically correct. He is just an a**h*** and you should never waste time on such people.
I agree, the irony is such people are looked positivity by management