Strawberry Jam is an amazing project made by many talented people in the Celeste community. The soundtrack is great and a lot of the levels are full of personality and unique gimmicks. It's also a good place to learn new techniques and practice them in the built-in tutorial sections.

Unfortunately I'll have to take a star off because some levels have annoying gimmicks or are just straight up unfun at times, but it's to be expected for a collab to have a few bad apples every now and then. Please don't let this demotivate you, as the experience in every level differs from person to person and Strawberry Jam is definitely worth your time.