Star prepares for the Midnight Warrior Blowout Sale at Quest Buy.
Star and Marco are attending the "10,000th Squire Blowout" at Quest Buy. Knights and their squires run about the store collecting items in the allotted time. Marco immediately befriends the other squires who came with their knights to prepare and reveals his list which contains all the important items that every squire should get their knight. Higgs, a young overconfident squire, praises Marco's preparedness and even gives him some advice. However just before starting, he overhears her calling him a nerd. Star and Marco get ready with their carts, but just when the blowout begins, their cart's front wheels come undone; revealed to have been sabotaged by the other squires. Marco deduces that they will try to get all the better items before them and plots to try and outwit them, though Star does not seem to care and just wants to collect random items.
Star and Marco attempt to get a shield plate (where the last one gets dented), a starter horse (which is stolen by Higgs; followed by all of them getting taken by another squire) and dragon repellent (where Higgs rearranges the signs so Marco accidentally gets dragon attracter). Marco stops Higgs and demands to know why she is being a jerk to him. She reveals that she has had to work non stop to be a squire to her knight, Sir Stabby, and that she takes her position seriously. She accuses Marco of getting to be a squire because he is Star's "boyfriend". When he denies that he is her boyfriend, Higgs tells him that he got it out of pity then. Marco ramps up Star to get armor waxing and after an intense race, Marco manages to get it, though he severely injures Higgs. Disappointed in him, Star gives the wax to Higgs, who turns around and insults them.
Marco feels terrible as he just wanted to be the best squire he could possibly be for Star and not make her look foolish. She tells him that she does not care as she is a princess, not a knight, and she bent the rules so that they can hang out with each other. They learn that they only have one minute left and Marco decides to make the best of it for Star. Back at the checkout (where it is shown that Higgs does not get much respect from Sir Stabby) everyone is set to pay when Marco and Star arrive with a cart full of silly objects. As they play with each other using the strange products, Sir Stabby admits that he is impressed, making Higgs jealous. Star and Marco continue to laugh over their assorted items.
- Eden Sher as Star Butterfly
- Adam McArthur as Marco Diaz
- Lauren Lapkus as Higgs
- Fred Tatasciore as Sir Stabby
- In Disney XD's initial announcement, the episode title was spelled as "Trial by Square".
- The title is a reference to the phrase "trial by fire".
- The toy gnomes that Star and Marco buy bear a strong resemblance to the gnomes from Gravity Falls and Phineas and Ferb.
- Star and Marco's line "Yes. Yes, we did." might also be a reference to Phineas and Ferb.
- Despite only having a major appearance in this episode, as well as a brief reappearance in "The Knight Shift", the character of Higgs has gone on to be a fan favorite with many considering it a disappointment that she was hardly used in the series' run.