Pac-Man is a Creature from the Game Pac-Man. The object of the game is to get Pac-Man to eat what is known as a “pac-dots” or “pellets” before the four ghosts in the game (named Blinky, Pinky, Inky and Clyde) reach him and after a while (when he looses all his lives), make him loose the level. If the ghosts don’t reach him by the time Pac-Man eats all the “pac-dots” or “pellets”, and Pac-Man goes to the next level.

So what Das-EFX is trying to say is they eat a rapper like how Pac-Man eats “pac-dots” or “pellets”. Also he may be saying that he goes to the next level of MCing, as Pac-Man does once he completes a level.

Fat Joe is a rapper from D.I.T.C. In this line he is using a slang homophone of Fat, which is “Phat”. To call something “phat” is like to call something cool, fresh, fly etc. He is playing with the word, to make it mean both things.

Evergreen in this case would be slang for weed.

Fat Joe and Lord Finesse are both fellow members of the Diggin' in the Crates Crew (D.I.T.C.), along with Diamond D, O.C., Buckwild, Showbiz, A.G and deceased member Big L (R.I.P).

Fat Joe said the following during an interview with Complex:

Lord Finesse was who inspired me to even rap. So at that time, I thought Finesse should have been on that record. So I think subliminally I threw a little shot, and was like, “Motherfuckers know who’s the best, if it ain’t Fat Joe then it must be Lord Finesse.’ That was letting them know, ‘Yo, that’s my brother, and I don’t know what he ain’t doing on this. But he deserves to be on here.

He is walking around with a gun, more specifically a TEC-9