Skeletal Champion Growth

[Kulmara]

I'm working on a Lich build, but my only problem is that I don't know enough about the Skeletal champions. Specifically how they grow whenever I gain a mythic rank. Do they gain levels equal to the ones required for the rank when respecing? And if so, what feats do they gain?
I want my Lich to be a caster that uses a scythe when enemies get to close, and the Lich is great at healing undead allies. But that also means I need someone to be the tank. At the moment I am considering giving that role to Ciar, but I don't even know he starts with. So currently I think my Skeletal Champion will have to fill in that role, but I don't know a thing about how he will improve later.
Can someone tell how each Skeletal Champion improves as I rank up?

[seeker1]

There's a decent guide to the Skeletal Champion at Fextralife.

https://pathfinderwrathoftherighteous.wiki.fextralife.com/Skeletal+Champion

It gets an upgrade to a second "class" at MR 8.
https://pathfinderwrathoftherighteous.wiki.fextralife.com/Skeleton+Upgrade+Selection

Dunno why this isn't all on one page.

[x_equals_speed]

You don't get to level your skeletal champion yourself and the auto leveller will waste all of its feats on stupid options that aren't compatible with each other (Mine has taken armour focus three times for the three different weights of armour!)

It's also currently bugged so if you make it a cleric its "Channel energy as a cleric with level equal to your hit dice" thing will treat it as level 1 no matter what.

Whatever you do it will never have a good INT so it's not going to be much good as an arcane caster.

It's also no good with buffs (Since it doesn't get mythics and can't extend spell) or debuffs (Since it wastes all its feats and won't spell penetration or spell focus).

With those options off the table the remaining effective choices are: Load it down with activatable magic items or make it a bard so it can tootle and make enemies constantly shaken.

Activatable magic items are also bugged in turn based and won't let you activate them once a fight starts.

*toot toot*