Grothama, All-Devouring also considers the following cards to be candidates for inclusion.
In a more aggressive version of the deck, expendable creatures with low CMC and high power could be used in place of protective effects, if Grothama is only played just before attacking for card draw. Good choices include Durkwood Baloth, Phyrexian Soulgorger, Rhonas the Indomitable, Ravaging Riftwurm, Managorger Hydra, Traxos, Scourge of Kroog, Hunted Troll, Kalonian Hydra, and Gigantosaurus.
Hypergenesis acts as a second copy of Eureka, but needs to be suspended a few turns in advance, and can only be cast during upkeep, so Reliquary Tower and Greater Good are helpful to increase its potential. Mosswort Bridge allows us to cast it at instant speed without suspending.
Ugin's Nexus gives us an extra turn to capitalize on a Eureka or Hypergenesis, but needs to be destroyed by a Terastodon or something similar.
Tornado Elemental can wipe out most flyers that opponents put into play with Eureka. Bane of Progress and Oblivion Stone could also be good with some sort of indestructibility for our permanents.
Kozilek, the Great Distortion, Void Winnower, Nullstone Gargoyle, Possessed Portal, Dosan the Falling Leaf, and Conqueror's Flail can prevent opponents from responding.
Alhammarret's Archive lets us draw twice as many cards from Grothama. Strionic Resonator can do the same and also copy other useful triggers. Abundance can be useful to only draw nonland cards, or find the seven land cards needed to flip Sasaya, Orochi Ascendant.
Cloudstone Curio is another way of bouncing Grothama after fighting to draw cards. It can also bounce mana producers like Selvala, Heart of the Wilds and Karametra's Acolyte to produce more mana if we have Swiftfoot Boots to provide haste.
Vedalken Orrery and Yeva, Nature's Herald allow us to flash in Grothama just before our turn so opponents don't get to fight it when they attack.
Silent Arbiter prevents opponents from fighting Grothama with more than one creature so it's much harder for them to kill it.
Shield of the Avatar can negate the damage to Grothama from most creatures and allow it to block, or protect our own creatures when they fight Grothama, as long as we have enough creatures to amplify the damage reduction.
Dolmen Gate protects our creatures from combat damage when attacking, preventing blockers from drawing cards by damaging Grothama, or killing our creatures that survived fighting Grothama.
Scythe of the Wretched equipped to Grothama returns the first creature killed by it, which can save our creature and deter opponents from fighting it, although they can fight it with fodder first to unequip the Scythe.
Umezawa's Jitte can pump Grothama, or shrink and remove opponents' creatures.
Nantuko Mentor can deter opponents from fighting Grothama with the threat of pumping it, and then pump another creature on our turn to safely fight Grothama and draw double the cards. It also makes Grothama deal lethal commander damage to an opponent in one hit if we can give it at least 1 more power, as does Berserk, Grappling Hook, Fireshrieker, or Inquisitor's Flail.
Grafted Exoskeleton makes Grothama lethal in one hit. Detaching the exoskeleton from Grothama also lets us sacrifice it to draw cards if it is damaged.
Conjurer's Closet can flicker Grothama to draw cards after we deal nonlethal damage to it, but only works during the end step.
Mirage Mirror can copy any useful permanent, often providing a non-summoning-sick copy we can tap immediately, and is especially lethal when copying Pathbreaker Ibex then attacking with Grothama. It can also copy Grothama to let us sacrifice the original to draw cards, which is helpful when Grothama is indestructible.
Dual Nature copies the creatures we play or cheat into play, and also makes copies of opponents' creatures, but we should benefit asymmetrically. Bramble Sovereign makes a copy of our creatures entering play for .
Helm of the Host makes copies of Grothama that we can fight to draw cards. Fighting the copy with the original can draw 20 or more cards.
Soul of New Phyrexia can protect all our permanents from boardwipes, especially instant-speed ones after a Eureka.
Eldrazi Monument makes all our creatures indestructible fliers, but requires other ways to make Grothama leave the battlefield for card draw.
Colfenor's Urn can bring back Grothama and our other big creatures, but can backfire if the Urn is destroyed while Grothama is exiled.
Cauldron of Souls revives Grothama and our other creatures it fought so we can draw cards without much downside, although Grothama will now be around and smaller for opponents to fight until our next turn.
Deathrender can cheat all the creatures drawn from Grothama into play as long as there are enough creatures to sacrifice, especially with Ashnod's Altar to negate the equip costs.
Bear Umbra protects one of our creatures when it fights Grothama, and untaps lands to cast the spells drawn when Grothama dies. Nature's Will also untaps our lands after combat.
Stone-Seeder Hierophant gives multiple untaps with Paradox Engine or landfall triggers from Eureka, generating lots of mana by repeatedly untapping Gaea's Cradle or Nykthos, Shrine to Nyx, or repeatedly untapping Oran-Rief, the Vastwood to massively grow the newly played creatures.
Circle of Elders and Whisperer of the Wilds produce a good amount of mana if we have at least one other big creature. Priest of Titania and Elvish Archdruid could ramp well if we had a few more Elves. Shaman of Forgotten Ways ramps while providing an alternative wincon.
Emerald Medallion reduces the cost of our green spells. Rhonas's Monument can further reduce the cost of our creature spells while pumping and granting trample. Geode Golem can help us cheat Grothama into play after it has died multiple times, and has reasonable power.
Sekki, Seasons' Guide can leave behind an army of Spirits after fighting Grothama, or return from the graveyard instead.
Siege Behemoth lets our creatures bypass blockers. Champion of Lambholt or Bellowing Tanglewurm make them nigh unblockable.
Brawn easily gives trample to all our creatures when it attacks by fighting Grothama and dying.
Wurmcoil Engine gains life when fighting Grothama, and leaves behind more Wurms.
Nylea's Colossus can double Grothama's toughness so it can take more punishment, or double another creature's power so it can deal more damage to Grothama and draw more cards.
Death's Presence pumps our surviving creatures when Grothama fights.
Foe-Razer Regent grows our creatures if they fight Grothama and survive. It also makes Grothama bigger, but we don't get card draw if Grothama doesn't die.
Deceiver of Form can transform Grothama and other creatures into something else so opponents can't draw cards from combat damage to Grothama, but it also prevents us from drawing. This is very lethal if Pathbreaker Ibex is on top of our library and we have 3 or more creatures ready to attack.
Hunter's Prowess is a second copy of Hunter's Insight, with the benefit of +3/+3 and trample, but with the drawback of sorcery speed letting opponents know which creature to block.
Elemental Bond draws a card for each big creature we put into play, but is a mandatory draw. Abzan Beastmaster draws a card each turn since we are likely to have the biggest creature. Beast Whisperer draws cards when casting creatures but not when cheating them in.
Skullclamp can provide bonus card draw when Grothama or our other creatures die, and can convert tokens from
Druid's Call, Broodhatch Nantuko, and Saber Ants into lots of cards.