This deck is primarily a 1 on 1 deck, but it would still probably do well in a 3 player game. One major issue is that a player can't just sacrifice a permanent. That condition must be granted to it by a card other than Mazirek.
This makes these enchantments into staples:
1.
Awakening Zone - Every turn brings permissibly sacrificial Eldrazi token.
2.
From Beyond - Again every turn brings a permissibly sacrificial Eldrazi token.
Also, I believe that in all green infect decks adding pump spells like
Invigorate (for no cost opponent(s) lifegain means nothing, because this game is about poison, which is different). Pumpers like Groundswell, Phytoburst, Vines of Vastwood, and Might of Old Krosa, also work very well.
There are some sacrificial artifacts like Elixir of Immortality, Traveler's Amulet, Nihil Spellbomb.
There are also some sacrificial lands as well like, Terminal Moraine, Terramophic Expanse, Evolving Wilds, and Panoramas.
Throne of Geth is very important as well because it enables any artifact to be sacrificed.
Another idea is to cause other players to sacrifice permanents, thus beefing alreadry incredibly powerful creatures with infect. In commander, the rule still holds that only 10 poison counters must be dealt for a win. That means that a infect creature of the same power and toughness is 4x as powerful as a creature that does regular damage. However, it is 15 poison counters that must be dealt for a win in a game of 2 headed giant.
Turn smaller creatures into behemoths by using cards like Gigantiform, Epic Proportions, Overrun, Overwhelming Stampede, and Creeperhulk:
Suddenly Glistener becomes an 8/8 trampler, with infect. That plus the rest should be enough to put just about any opponent away.