The mousefolk in particular are known for their pluck and bravery, and when the call to adventure comes, they tend to answer
These cards are powerful enough that they become staple cards in competitive or serious decks
Four-Colour Control has plenty of ways to counter spells, but can also remove problems with cards like Temporary Lockdown
I don't believe either of those rules are in contention for the top spot of "old rules that would still be be sweet to use in oldschoolmtg", but that is a fully different post
They were first introduced with Throne of Eldraine in 2019, and they exist for one reason: to give collectors and foil chasers a concentrated dose of the best-looking cards in a set
Each includes a 60-card deck composed of two of the six possible ink colors, cardstock damage tokens, quick start instructions, a paper playmat, and a booster pack