For your consideration, here are my picks for the top mass pump spells in Magic you can use to convert twelve 1/1 Goblins, Soldiers or Rabbits into a victory
Increasing Damage However, no matter how many direct damage cards I add, the commander starting life total is 40
Sinister Waltz is a great multi reanimation spell as well that can also help get back something to your deck for later, though I think it's a little medium in a deck where the commander himself is already doing a lot of reanimating
When Forsaken Crossroads enters the battlefield, scry 1
As if this werent enough, thanks to having partner, Rograkh decks can flexibly utilize whatever colors a player may want in their deck
Nyx Lotus in a mono (or sometimes two) color deck can tap for at least three mana, and should it stick around, it will probably help you keep casting your Commander for the rest of the game