There's an Elemental Specialist Wiz that can turn all damage into the Element of your choice at level one and then turn half of that untyped at lvl 15 which goes well with the Ascendant Element Mythic which makes the Element of your choice irresistable and cancels immunities.
Yep. But which mythic path do you suggest? I will pick an elemental specialist wizard. Just imagine maximized/empowered sirrocos dealing cold damage which are much better than fire.
Lich. Spellbook merging is that good.
In that sense it’s too good. I think to enjoy the tempo of the game you’re better off with Azata Zippy Magic but Dhampir Lich is probably better thematically?
I mean you’re INT-based so Trickster has some good features and nukers go better with Aeon than debuffers and controllers.
The question was which Mythic one might recommend for a 'cold-based wizard'. Without knowing anything about said character one can either give the answer that fits a min-maxed character (Lich), a very generic version of the character fantasy (which is also Lich ie cold powers from beyond the grave + necromancy) or simply the one whose mechanics are the most synergistic with cold-based wizard (Lich as well, spellbook merging isn't just powerful it integrates itself with every aspect of the character).
Once you know how far you can go, you understand how you can partially ignore min-maxing in the name of a character concept. But to know where to go from here requires that the character be more than just elemental specialist wizard that maximizes cold damage.
Most Mythics can mechanically support a caster wizard. From the top of my head:
Azata's Zippy Magic doubles every single target spell. That's rays and single target DC spells like Icy Prison. Favourable then helps a bit with those enemy saves.
Angel's Sword of Heaven can boost attack spells as well as give you free quickened castings. As well as all the utility that comes with a 20 CL cleric spellbook. It's like a Mythic Theurge with no delays.
Aeons can boost summons, boost dispels and help with rolls against chaotic enemies (so, everyone). They also give you free quickens.
Demon's spotlight is having the best DC boost in the game capping it off at a +8 with rage.
Trickster can use Sneaky Quack with Vampiric Shield, can use Knowledge World 2 and Crit related feats to boost rays and gets some interesting spells from their (sadly, magus) spellbook. There's a lot to them, which is brought down by opportunity cost (first Greater Trick at Mythic 7).
It's just that Liches have it very good with spellbook merging and the unique things you can do with your undead party.