It's regigigas, but you'll need to capture regice, registeel, and regirock first.
I think it's a Regi.
Unfortunately, even though there are 493 Pokemon as of the release of Pokemon Ranger: Shadows of Almia, there are not 277 Pokemon in the game and therefore not a Pokemon numbered 277. The Almia Browser goes up to R-267 (Regigigas). Even with the option of Wi-Fi events making an extra three Pokemon available, it still does not equate to having a Pokemon numbered R-277 in the Almia Browser.
regigas
THERE ARE 267 POKEMON IN TOTAL
You can get 267 Pokemon, you can get 3 Pokemon within Wi-fi missions, that gives you 270 Pokemon.
Pokemon 267 is Regigigas. After obtaining all 266 pokemon, you will find him in Hippowdon Temple in the room with the tiles with arrows on them. There'll be a whirlpool in the middle of the room. Go in; you'll find that you need to catch Regirock, Regice and Registeel to get to him. Once you do, be careful as Regigigas is a very hard capture.
Pokemon nr. 267 is Regigas. Its in Hippowdon temple. Only as boss after capturing all 266 prior pokemon. Good luck! ^^
regigigas
REGIGIGAS (i've completed the browzer)
it is regigigas to get it, you need to have seen all 266 Pokemon, but 1 will be missing so go to the union. there, you will learn stuff about a vortex in hippowdon temple. go catch regice regirock and registeel then go to hippowdon temple and once you see the vortex, go in. place the Pokemon on the pedestals and go in the room. be careful, because wherever regigigas steps, it causes and does damage then once you caught it be happy as you have finished the game. Hope this helps
you can't catch regigigas but you can battle him.If you want to battle him,look at these instructions.They should work because i did it.First complete all quests.there is a quest that appears after you complete all other quests.you have to do that especially.then get regirock,regice and registeel.there will be a whirpool go into it.if there is not a whirlpool, go into the ranger union then try again.go forward and press a at each picture.then a door will open and go in.it will ask you yes or no if you want to go in.choose yes.you will see regigigas punching then will face you.(warning regigigas is a boss.try to catch all the magneton you see to help you win.you won't have him but you will get a thing etched in your styler.you can face him even after you beat him.but he is really hard.hope this helps!)
with pokeballs