I suggest that you enlist 4 fully grown men that weigh at least 200 pounds each and carry it down the stairs.
They should be healthy with no back issues or other problems along that line.
Perhaps if you fit that criteria, you only need 3 more.

Just be aware that some of those games are especially heavy.
You might even want a 5th small person to hold the door open, hold the power cord or give the big guys water or whatever.
Guys in that weight range will probably need something to eat too before the deed is done.