Brick

Brick is the one Trinket you can still earn today whose whole effect is a penalty. It lowers walk and run speed by 10%, and the effect text itself adds that it is a brick, so what did you expect. A 5-star Toon drops from 20 walk and 30 run to 18 and 27, and a 1-star Toon from 10 and 20 to 9 and 18. Nothing in the data offsets that loss.

The only reasons to equip it are a self-imposed challenge or a joke build. Shrimpo, who has 1 star in every stat, is the obvious pairing, since the Trinket comes from Research on Twisted Shrimpo and the icon shows a note reading that he hates bricks. The numbers are harsh: of the 37 Twisteds with a listed chase speed, 26 chase at 18 or faster, so a Brick-wearing 1-star Toon is outpaced by most of them. A 5-star Toon at 27 still beats all 37, because the fastest chase speed in the roster is 26.

Twisted Shrimpo is a Common, so the Research is quick to finish: Commons make up 75 of 110 spawn weight at the start. There is no Ichor cost.