Cool!

Hydras and x-spells have always been an interest of mine, but I never truly found the correct commander - trying decks such as Kenrith, the Returned King and Rosheen Meanderer. Many of these cards can be seen as just "fun" cards, but, as with everyone, take with a grain of salt!

I prefer Pull from Tomorrow over Mind Spring because you are often casting it for enough where the discard is worth it for instant speed.

Kruphix, God of Horizons or Doubling Cube might be worth it. Also, mana doublers, such as Mana Reflection or Vorinclex, Voice of Hunger might be worth the slot. Animist's Awakening is interesting and on the x-spell theme.

Mind Grind for another win-con.

You could also include the Urborg, Tomb of Yawgmoth / Cabal Coffers package along with cards like Vesuva and Thespian's Stage for even bigger mana. Then you could include fetches for these cards, such as Tempt with Discovery, Hour of Promise, and Expedition Map, although sort of slow.

Possibly, Rishkar's Expertise for big draws and a free play. Thrasios, Triton Hero for obvious reasons. Maybe even token doublers like Doubling Season

I don't really like Finale of Devastation or Green Sun's Zenith for Hydras, because whatever creature you get generally just dies when it enters the battlefield. The Talismans are cool, but pure, land-based ramp might be worth more in the long run, especially if you decide to add the cheaper mana doublers. The land base might be a bit overkill for a three color deck with access to green. In my experience, I can often get away with running more basics in sultai, but if it works, it works. Maybe Chromatic Lantern would help?

These are just my quick thoughts. Kind of sad that this commander doesn't have red. I haven't reviewed your recent edits, but I would like to hear more about what you are thinking.

Good call on Pull from Tomorrow over Mind Spring, I'll make that swap.

I really went back and forth as to whether to include both Green Sun's Zenith and Finale of Devastation due to the X cost factor you mentioned, but I ended up adding 3 powerful non-X cost hydras to take that into account. That said, as my options are so limited there I think replacing them is the right call. I want to keep the X spells count up so I may try Open Into Wonder and The Crowd Goes Wild for a couple of hefty surprises.

I wasn't drawn to the Doubling Season effect cards for 1 simple reason - the double tokens produced by Zaxara will enter as 0/0's and will fizzle. That said, they may be worth running for the additional +1/+1's, we'll see how well Hardened Scales performs and if I feel as though I want redundancy for that effect I'll look to add them.

Lastly, mana doublers. Yeah, probably a good idea for maximizing those X casts. I'm leaning toward Mana Reflection and Zendikar Resurgent.

Great ideas Manley1994, thank you - I'll be incorporating a few of these for sure.

Both Pemmin's Aura and Freed from the Real let you make infinite mana with your commander. Walking Ballista is another removal option.

Oh my. Yeah, those 2 cards open up a world of infinite shenans for sure. Gonna sneak them in here, nice one DankMagicianD.

Nice list, definetly worth adding a Doubling Season and Parallel Lives. So far love this set and commander 2020 as well. Plenty of goodies for both. Can't wait to see this commander in action along with the Sultai Apex and Face of the Commander deck.

Yeah you're right Bloodsucker1211, the +1/+1 doubling alone is going to be worth it. Going to have to give some thought as to what to cut to make room.

As an alternative to Doubling Season or Parallel Lives, you could include Corpsejack Menace. It's a creature so its removed more easily, but at the same time, for the same amount of mana you're also developing a body for protection while you're getting your commander and X-cost cards set up. Essentially you're trading the ability to double tokens (which as you mentioned already fizzle out) for a 4/4 body.

Also, Corpsejack Menace is considerably more affordable than Doubling Season or Parallel Lives.

Cheaper casting cost than Doubling Season as well. Sounds like a smart call Xephon_, good thinking.

Forkbeard I'd also like to introduce Endless Scream. Fantastic little buff and you get a hydra from it.

Endless Scream seems like a decent spell buff. Maybe!

Hi there! Just one question: why no 1 mana dorks like Birds, Deathrite Shaman or Elves of the Deep Shadow? (Over the signets, for exemple...?) Kira's Follower also comes to mind as synergistic with Zaxara.

Seedborn Muse might not be a bad idea. Lets you dump everything into x spells while keeping answers up during opponents turns, keep up maximum aggression while keeping up your defenses with the pseudo vigilance, and the occasional extra value by being able to weave in x cost instants is nice especially on x cost counterspells. Would be hilarious too just to dump all your mana into Simic Ascendancy on everyone's turn too.

As a fellow lover of many-headed monstrosities I'm glad to see some new blood for Hydras in Ikoria, as much as it saddens me that Zaxara won't go into my Hydra passion project (Selvala, Heart of the Hydra).

I'm going to build a Zaxara too and looking at your list, the only thing I'd change right now is Ironscale Hydra who didn't even make the cut in monogreen. Maybe the new Goat-hydra who seems fun, Hooded Hydra for MANY MANY MANY SNEKS or just Polukranos, Unchained since you have the right colours and he's recurrable removal.

Golgari Signet, Dimir Signet, and Simic Signet might be better stones, They're cheaper without the pinging yourself, but also have the advantage of adding 2 mana which synergizes better with Nyxbloom Ancient and Mana Reflection

Manocos: Personal preference, but I typically prefer rocks over dorks as they're a bit stickier. That said, a couple of clutch 1 drops might be worth it - Birds of Paradise is a fave of mine.

wildcardde: Yes! You're on to something there! May slot in Seedborn Muse to max out the instant speed advantage + defense + Simic Ascendancy fuel, good call. Like TheMr42 says, Ironscale Hydra is just ok whereas SM would make for a much stronger 5 drop. Replacement confirmed.

TheMr42: I like both Hooded Hydra and Polukranos, Unchained, but I was on the fence with both of them in here. I suppose the sneks could be fun, particularly paired with Doubling Season and/or Overwhelming Stampede/Triumph of the Hordes. Food for thought, for sure.

jinkuzo: Ah, the signets vs. talismans debate. They're both great, I just find the talismans are a bit more efficient in a pinch. Edge case scenario for sure, + I like your rationale alongside NA + MR. I threw the talismans in here for now but am thinking about different ramp options too, such as the aforementioned BoP et al.

Thanks for the thoughts & suggestions here everyone, some good discussion.

I have a Saheeli X spell deck, but Zaxara really piqued my interest when I saw it. Everyone loves hyrdas, and getting board presence of big X spells feels great.

Astral Cornucopia will help your mana and give you a token - It's a steep cost but does fit the theme.

Mass Manipulation has been a powerhouse for me in Saheeli. I appreciate the might be harder for tri-colour, but Zaxara helps with that a lot.

Hangarback Walker and Walking Ballista are again big X artifact spells, the latter able to win you the game with the infinite mana combo.

Bloom Tender - If you are running Freed from the Real and Pemmin's, then he is a backup inclusion for the infinite mana route.

Chimeric Mass is a nice way to protect your creature based board from sorcery speed sweeps.

Battle at the Bridge, Death Wind, Disembowel, or Erebos's Intervention offer X based spot removal to compliment your X based counterspells which I like the inclusion of here!

Dark Salvation works as smaller creature (depending on your mana) removal and generates you some additional tokens

I love the discourse on this! Kindred Discovery looks amazing in this.

I'd encourage you to look hard at the new cards in Commander 2020 for some extra oomph. Species Specialist allows you to draw cards off of Hydras kicking the bucket (could be a nice card draw engine from Greater Good), Cazur, Ruthless Stalker  ^Flip pumps your Hydras up for each successful combat hit to a player (also boosting Simic Ascendancy).

Also, Biomass Mutation just looks rude for this.

Lots of interesting options there PolarBearSoup, thanks!! Bloom Tender & Walking Ballista in particular seem like real worthy inclusions. I have a copy of Bloom Tender in my Roon deck that I think I'll re-purpose to here - on top of just being an amazing mana dork, combo redundancy is wise.

Thanks Paeldroth. I haven't had time to decipher the new decks yet apart from Zaxara (heh), the other core generals/legendaries and the 'free' spell cycle (those look awesome btw). I'll need to tuck in and investigate, but those 2 cards you listed are interesting.

I keep going back and forth on Biomass Mutation but I should probably test it as it's certainly on theme. Really wish it granted trample too, greedy!

Somehow missed the Zaxara spoiler before now, but found out about it when I saw the freshly spoiled The Ozolith, which obviously plays very nicely with this commander. Got me excited to start putting together a similar decklist.

Some cards that I've been thinking about:

Growing Rites of Itlimoc  ^Flip seems like potentially good ramp.

Death's Presence is good against spot removal.

Not a hydra, but Stonecoil Serpent is efficiently costed.

Was thinking about Mana Bloom, but forgot it was only once a turn, probably not worth it.

Holy shit, The Ozolith! Hadn't seen that card yet and I love it, seems like a very fun 1-drop inclusion in here. Great suggestions OneSwellFoop, thank you.

I feel like the signets should still have a place here. They are great for color fixing and when you tap them for mana, your two multiplying effects would still go off because they say permanent, not land. So one land gives you 2 mana. You load two signets and have 8 mana out of nowhere. Or even one land for 3 mana and load 3 signets for 18 mana out of nowhere. They can get out of hand fast. Id suggest going down some lands for the signets. They hold a lot of value and you have mana fetches. So as long as you keep a smart hand, you should be all set.

I'll second what OneSwellFoop said about Stonecoil Serpent. Not a hydra, but an X value spell that doesn't care about mana color. Plus protection from multicolored is nothing to scoff at.

And yeah, The Ozolith is pretty fantastic. I think these decks will just get better.