Not sure I can say I have any particular favorite. I suppose Nintendo would be overall, but that's not quite fair to smaller developers. I do like Grasshopper Manufacture, or more specifically Suda51. Konami's made the MGS games which I love. Retro made the Metroid Prime games, as well as Donkey Kong Country Returns. Speaking of, Rareware used to be great. Same with Square Enix. Clover made the excellent Okami before it shut down, and similarly Cavia went under after having made NieR. I haven't played most of their games myself, but Valve seems to have considerable talent. Between the Saints Row and Red Faction games, it seems Volition has done pretty well.
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About suffering they were never wrong,
The Old Masters: how well they understood
Its human position; how it takes place
While someone else is eating or opening a window or
just walking dully along...