What are some alternatives?
When comparing Super Phantom Cat and Hollow Knight, you can also consider the following products
Super Meat Boy - Let's start with what's the same: Dr. Fetus is still a jerk, gameplay is super challenging but fair, there are tight controls and great levels and you will die. a lot.
Downwell - A game about a young man going down an endless well with gun-boots
SuperTux - SuperTux is a classic 2D jump'n run sidescroller game in a style similar to the original Super...
Minilens - Libre puzzle platformer for gravity-oblivious aliens
Braid - Resource planning & scheduling for professional services
Mari0 - What happens when you mash Super Mario Bros. and Portal together?