SUPER ANIMAL ROYALE

Health Juice is found around the map and you press Y to use it

In video at 5:30
Achievement Walkthrough:

I found that waiting until the circle is done moving and then going in and out over again worked pretty well for me. Can be unlocked with normal gameplay though.

Health juice bottles can be found scattered throughout the map in various rooms/areas and if you move through the grass, you'll gain an abundance of them. Another specific area with lots of them is the Health Juice Factory. And if you find the Super Juicer, the maximum cup upgrade, on the map, you'll be able to hold 300 health juice at once. One way to work towards this achievement is to damage yourself with Lucky Cat Mines, grenades or explosive barrels without killing yourself and then use the health juice to heal yourself, rinse and repeat. But a faster way that allows you to accumulate massive progress each match is to load up on health juice to your full extent and simply stand just outside the circle, using it with , while taking damage. If you do this using a full Super Juicer, you'll gain 12% worth of progress towards the achievement.