[Squirrelloid]

The following things stand out to me:
(1) You were even in research with Ulm. As pythium. You should have been *leaps and bounds* ahead of him in research. You should have been matching his Alt6/Const6 with Alt 9, artifacts, and high conjuration or evocation. Pythium has no excuse for being only tied with Ulm in research.

(2) Fatigue spam definitely works. Specifically the 'no MR' kind. Thunderstrike is pretty good (<100 SR is not enough). But Solar Cascades is the real star here, and *every single pythium mage worth a damn* can cast it without communioning.

(3) Losing your armor? Marble Warriors/Army of Gold/Army of Lead is the best response. And you should have the research advantage to pull this off. If you're still relying on regular troops by the time Ulm has multiple 6 level research, you absolutely need at least one of these spells in every fight. Being able to drop AoG/L round 1 can also pre-empt earthquake to a large degree.

(4) Fog Warriors. Every fight.

(5) Mist of Deception could also be a pretty disruptive spell.

(6) Summons to use:
-Manifest Vitriol (can you tell I love alteration yet?)
-undead like Wights can work (admittedly not so much for pythium). Anything less than 100CR is going to fatigue out, and wights are pretty solid infantry otherwise.
-Mechanical Men or Living Statues make for a resilient frontline that isn't especially vulnerable to armor destruction.
-Thugs with good defense, good magic armor, and AoE weapons.

(7) Other spells of note:
-Acid spells are relatively accessible to Pythium, and ignores all elemental resistances, and damages armor!
-Your armor getting destroyed? Return the favor! Destruction isn't full battlefield, but its still brutal.
-Magma Eruption is only half fire. The other half doesn't care about elemental resistances.
-Ice Strike is *not* cold damage, and with high W level (you are communioning right?) it has a decent AoE.

(8) Communions!
-Use master matrices to start your master(s) communioned. They can spend their first turn casting a defensive spell, which will apply to all the communion slaves that cast before it gets to him. This can help with earthquake survival. (If you drop Twist Fate on all your mages turn 1 via communion, that earthquake isn't going to do much).
-Use communions to boost variable AoE spells into uber territory.
-Even spamming something simple like Enslave Mind or Soul Slay will overcome Ulmish MR, however slowly.

(9) Don't limit yourself to fighting during the battle phase
-Combats in the magic phase can prompt gem use, exhausting key mage's supplies before the main engagement
-Flames from the Sky / Fires from Afar / Seeking Arrow / Murdering Winter can potentially take out key leaders or wreck army formations. Fires from Afar is a 25+ damage ap fire attack that will hit without the benefit of those pesky OBSes - if it hits a mage the mage is toast, and even Ulm's troops are going to risk death from a hit.

(10) Ranged weapons
-Xbows, commanders with bows or xbows, or otherwise apply range pain. The non-tower shield infantry are vulnerable to missile fire.
-Fire Arrows