Character: martlet (undertale yellow)
Martlet is a blue avian monster from the fangame Undertale Yellow. She has a two-tone body of blue and light-blue. Her attire consists of a shirt the same colors as her body, blue jeans, and yellow boots. Her name is a reference to the Martlet of heraldry.
Martlet is a member of the Underground's Royal Guard - a team of elite monsters whose job is to kill humans that fall into the Underground and take their Souls for King Asgore.
Stationed in Snowdin, she is responsible for constructing and maintaining her area's "puzzles" for whenever a human arrives. She learned her construction skills from being Chujin's apprentice. She is enthusiastic, highly intelligent, and somewhat scatterbrained.
Unlike the other royal guards, She is rather kindhearted and sympathetic towards humans, and isn't convinced by the kingdom's propaganda that all humans are essentially evil creatures. She helps Clover in their adventure whenever she can. Should Clover take a violent approach to dealing with monsters, she tries to persuade them away from killing.
The following are spoilers for Undertale Yellow:
Should the player attempt to complete the game's No Mercy route, Clover will be stopped by Martlet in front of the CORE, where she will reveal her fallback plan: A syringe of Determination she stole from Alphys's lab. By injecting herself with it, she transforms into a drastically more powerful version of herself, known as "the zenith of monsterkind." (See martlet_(zenith_form).) In this form, Martlet unleashes a relentless onslaught of attacks to stop Clover's rampage.
Note: Due to TWYS guidelines, this character should be tagged separately from Martlet's Zenith Form, unless the two forms happen to be in the same post.
This tag implicates undertale_yellow (learn more).