For this MCAL we are using Paintbox DK Cotton, it’s a nice thickness for making Amigurumi.
You can find a ready made yarn pack in 2 colorways (Pastel and Merry) on sale on Lovecrafts.com
(this is an affiliate link).
Please note the MCAL pattern is not included with the yarn pack and needs to be purchased separately.
But of course you are welcome to use a different yarn! This is a nice stash-busting project, as small makes don’t need as much yardage.