#since he seems immune to normal causes of statuefication. but being in an entirely different game could qualify as 'not fitting'

[mirror-ralsei]

PREDICTIONS: Ralsei

or, why this pile of rock is going to tear my heart out

Ralsei is a Titan.

"The unending pillar of darkness that gives my body form" dedication in Ralsei's manual matches Ralsei's description of Titans "tak[ing] form from the FOUNTAINS"

Ralsei's body completely disappears when downed

Ralsei was first completely shadowy and amorphous within his hooded cloak, then a bit more defined but still shadowy under his hat, before finally settling on a more visible form at the end of Chapter 1

Just before removing his hat, for a couple of frames Ralsei's sprite changes his paw color from black to white. As well, where Ralsei previously had black paws in various animations such as clapping or spell use, they are now white in Chapter 2. These suggest that Ralsei's shadowy appearance is not simply caused by the shade from his hat.

Ralsei's initial description is a somewhat ambiguous "Dark-World being"

Unlike normal Darkners, Ralsei does not turn to stone and can seemingly teleport between Dark Worlds at will

Ralsei is the sole denizen of Castle Town, an area seemingly abandoned or evacuated, where Titan-like eye marks and darkness covers the land

Ralsei knows a lot about the Roaring

"Do not be alarmed... I am not your enemy." is one of Ralsei's first words to Kris and Susie

Ralsei wants to redeem himself for participating in the last Roaring by stopping it from happening again.

Again: Ralsei is the sole denizen of Castle Town, an area seemingly abandoned or evacuated, where Titan-like eye marks and darkness covers the land

Ralsei’s portrait/sprite when talking about the Roaring seems haunted

Ralsei says “I...I’m sorry!!! I repent!!!” in the generally foreshadowy Poppup dialogue

However, Ralsei is an unwitting pawn in a greater villain's scheme.

Ralsei is characterized as overly keen to follow orders.

Poppup dialogue: “Ralsei moved to click on an ad with a bunny on it teaching you how to make friends... ...and accidentally clicked on an ad of a machine gun that appeared over it!” / “Ralsei tried to click on an ad with a castle on it... ...but it was actually an ad for a company that demolishes buildings with bazookas!”

Again: Poppup dialogue: “I... I didn’t mean to do it... I... I’m sorry!!! I repent!!!”

In order to fix his mistakes or save the world, Ralsei may sacrifice himself, perhaps becoming the Waterfall statue in Undertale.

Undyne states "That statue's been here forever... No one knows where it came from." This description seems similar to Gerson's explanation of the Delta Rune: "That emblem actually predates written history. The original meaning has been lost to time..."

The statue is greyscale and cracked, like Darkners such as Lancer when turned to stone

The statue has horns, like Ralsei (note that the direction of Ralsei's horns varies across sprites/portraits and concept art, sometimes being turned inward and other times outward)

The statue is associated with the song "Memory," which is associated with Asriel, who appears connected to Ralsei

The statue in Waterfall may have been part of the original Royal Memorial Fountain before Mettaton's statue replaced it

If so: Ralsei is associated with all three concepts of a "Royal Memorial Fountain," being a prince who is made from a Dark Fountain and, as "memory" is a prevalent theme in Deltarune and Ralsei sings its "Don't Forget" motif in battle, with remembrance as well

Other things:

Ralsei appears self-aware in the same way as Jevil and others.

"(SAVE and take a break anytime you want, OK?)"

"Even if it's not real, you can still have fun, right?"

"It seems like it was just a corrupted program."

There may be multiple "Ralsei"s in some way.

“They [two Ralsei plushes] are both correct. Both beautiful.” (Toby Fox on Ch 1 Livestream)

“Every Ralsei is equally beautiful.” (Toby Fox on Ch 1 Livestream)

“I just wonder what... being “Ralsei-like” even is...?”

Unknown: why does Queen not notice Ralsei?

“How Thoughtful You Two Have Come To Help Me / Kris, Susie / Which One Of You Wants To Be The New Knight”

“Hey Was There A Third Guy?????????”

“I Will Miss Each Of You / Noelle, Your Un-needed Honesty / Susie, Your Foolish Bravery / Kris, Your Chill Vibes / ... / B...Burghley?”

Unknown: why does Ralsei (seemingly) know about the ThornRing?

"..." if given

(screenshots: 1 2)

DISCLAIMER: this is a predictions post, just laying out the predictions that i have currently and my personal reasoning. eg. i am by no means the first or only person to consider titan ralsei rofl