Although they may not be the best answer for Infect, they are still solid cards in the matchup, so you can't dismiss them out of hand
Baleful Beholder Bhaal, Lord of Murder Breaching Dragonstorm Far Fortune, End Boss Fireball Ganax, Astral Hunter Glimpse the Impossible Horrific Assault Iron Golem Jeskai Shrinekeeper Karlach, Fury of Avernus Lae'zel, Vlaakith's Champion Lurking Roper Mind Flayer Mount Doom Nine-Fingers Keene Raphael, Fiendish Savior Reaper King Renari, Merchant of Marvels Sagu Wildling Sagu Wildling Sarevok, Deathbringer Sauron, the Dark Lord Shadowheart, Dark Justiciar Shessra, Death's Whisper Sivriss, Nightmare Speaker Sliver Overlord Stormshriek Feral Stormshriek Feral The One Ring The Tarrasque The Ur-Dragon Thrakkus the Butcher Xorn Zalto, Fire Giant Duke
Verdant Command Verdant Command offers some neat flexibility but it's too low impact for me to recommend it anywhere other than Squirrel Tribal, where making 2 squirrels at instant speed plus getting some other value is worth it
Theres a huge number of cards that spread -1/-1 counters and proliferate support, so youll be making lots of snakes in no time with Hapatra around