For context on Mary Sue,
The gods wanted a "hero" to bring hope to the world and revitalize faith into the gods, so Being X [The God Tanya hates] and other gods chose Mary Sue for she was the perfect vessel as she was both faithful, young, and had a hatred towards the Empire because her father was killed. They've done this before with Jeanne d'arc and other characters in history if you were curious why it seems familiar.

The issue is that Mary Sue is the opposite of Tanya in almost every way, on the surface it seems obvious who the hero is The gods were unaware their hero was already made, what they created was the Demon Lord.

Tanya inspires hope and faith in the Empire, the mad scientist becomes a man of the cloth because of her. On the other side Mary Sue destroys faith due to her naive actions and madness, many faithful due at her hands or her actions
Yes, Tanya in the eyes of everyone outside the Empire is the devil, but everyone in the world sees Mary Sue even worse.

Mary is super naive and gullible. Lilya is a political officer. She zeroed in on Mary being easily manipulated.

Mary: But they need to rest in their homeland.
Liliya: Precisely! This girl gets it!

mary never listened to the opinion of others, even her superiors, that's a very serious problem to have for someone with basically superpowers. she won't survive the war even if she survives the war

Lt. "Mary Sue"?!
That's........ Very on the nose😂

I've seen plenty of characters in other animanga series who hid behind a fake kind persona more convincingly than her

If Tanya's a "monster in the form of a little girl", then I guess that makes Liliya the adlt version.

She's like "so i can purge these mages when?"

>has a blue eyed blonde Tanya 'Tanechka' Degurechaff as  a battleground enemy
>gets groomed by blue eyed blonde Tanechka
>is named Mary Sue

The "KGB" handler for the trouble child federation revolutionary Mikel, just got a gold mine when mary sue showed up. Tho in way this is a presseure relief for LT Colonel Drake. All the bs he has to deal with from mary sue and her tantrums.

No one talking about that gross guy that randomly has a framed picture of Tanya?

2:37 I sense a disturbance in the force 🎉

The amount of times Mary was saved by the Script knows no bounds. She don't follow orders, don't have any self-control, don't work together with her comrades, and tried to face off tanya 2 times in a row. She should have died during their first encounter in the movie. But, the internationals are a bunch of hyprcrites, they accepted an impulsive enraged child in their army.

It's been years since I read the volume Lilya was introduced in, but I remember Mary Sue is supposed to be the antithesis to Tanya. She's innocent now, but once she's crossed paths with Tanya, she'll go rabid.

Tanya’s stalker 😰😱

She’s voiced by Hikasa Yoko! Rias Gremory from HS DXD 🤭

1:09 I feel like we would have had a heart attack if we see a time skip of Tanya.

Oh man when that happens Tanya is about to go on a warpath again

Oh look at that. A bunch of dead people talking. Go get them, Tanja!

If you second guess what her purpose is, it is as follows (not in order):
1. To make Russi Federation (USSR equivalent) look better
2. Prevent Mikel from revealing horrors of the regime, Spoilers! She's unsuccessful, he knows English.
3. Protect interests of The Party, even if it is militarily disadvantageous.

There is more, but it doesn't come to my head.