Brought Down to Badass: Due to destroying magic in the original series Metaora no longer has magic. She also is unable to grow in size like her father but she is still super strong and can unleash a Berserker Form when angry.
Seth of Septarsis
Ascended Extra: Though he was mentioned in the book of spells as the leader of the rebel monster fraction and waging war on all mewmans, Daron Nefcy herself stated that he was just created to provide more background information to Mewni and that he died long before the series. Here hes one of the antagonists and the leader of a Septarian gang.
Spared By Adaptation: As stated above he died before the original series. However, he is a cyborg and his enhancements seem to extend to his chest so it could be a matter of being brought Back from the Dead.
Would Hurt a Child: Punches and intends to kill Meteora and throws Mari against a stone wall.
So Proud of You: Both Eclipsa and Globgor express pride when Meteora rocks out on her old skeleton guitar.
Past Queens A.I.s
Back from the Dead: Subverted. They are A.I.s created from blueprints of the past queens of Mewnis neural circuitry which was engraved on the walls of the magic sanctuary after magic was destroyed. So they technically arent Star and Meteora's ancestors but they have their personality and memories.
Virtual Ghost: What they basically are, A.I.s with the memories of the deceased Mewni queens. Meteora even calls the Solaria one the ghost of her.
You Are Number 6: They have code numbers that identify them. For example, the A.I. Of Solarias code is EC-AI #28-9.
Been There, Shaped History: It is the same stump that the first Mewman settlers gathered around to survive a harsh storm and honored every year with Stump Day. However, it reveals to Meteora and Mariposa that it actually CREATED the storm in the first place.
Face Death with Dignity: While still angered when Mariposa and Meteora set it on fire it finds satisfaction knowing that it fulfilled its purpose of making people work together.
Revenge: The reason that it caused the storm was revenge for the Mewni settlers cutting it down.
Well-Intentioned Extremist: It traps people to force them to work and get along with each other. Yet still has no issue killing and eating those it considers a threat.