[Spoilers E62] How are Grog's stats so high?

I recently started watching critical role and have binge watched it up until episode 62 now - fantastic show! However, I noticed that at Grog's current level 14 (where I'm at) he somehow has 24 str, 15 dex, 20 con, 6 int, 10 wis and 13 cha, plus feats in mobile, and great weapon master picked at level 12 and an AC of 19. How on earth is it possible to have that high stats and two feats at such an early level? I know he has the Enlarge gauntlets for strength to 24, but I don't see how he can have that many points in the rest. Does any of you know how he got that many?