So many to choose from but I say BP2/TBA era.
BP2 is the #3 2x album OAT & features Hov's best lyrical performance of the trilogy & one of his best displays of bars ever, plus his Gawd MC flow was almost @ the pinnacle of perfection.
S. Carter Collection is the GOAT mixtape & again featured him spitting @ an insanely high level of godlike proportions & flowing his hump off in a way no MC in history could dream of.
Culminated in the GOAT rap album (TBA) with the GOAT @ the absolute peak of his powers in terms of his flows, bars & content all being on an gawdly level that will never come close to being reached again. Best MCing performance of all time & a classic that birthed the GOAT rap show (MSG) & documentary (Fade To Black).
Plus all them gawdly features he was doing at the time including blessing Bey, Cam, the Roc, etc. with the GOAT stimulus package.
If he never rapped another bar after that run he'd still be the GOAT, but thank god he choose to come back & add to his Gawd MC legacy.