It it not recommended to use this mod if you have epilepsy. Flashing Lights.

Cactus Juice 

How to Get Cactus Juice

Craft it: Put 1 Cactus + 1 Bowl in a crafting table.

 Or just right-click a cactus with an empty bowl.

Eat it for a quick 30-second buzz and some buffs.

How to Brew Cactus Potsions

Use a Brewing Stand:

Splash version: Add Gunpowder to any potion. Lingering version: Add Dragon's Breath to a splash potion.

What the Potions Do

All potions give you buffs: Night Vision, Speed, Strength, Jump Boost, Haste, Regeneration, Slow Falling, and Dolphin's Grace.

Your screen gets a rainbow overlay — shifting colors, pulsing rings, and flowing patterns. It's vivid but you can still see and play through it unless you brew the cactus into the mind-melting potion! 

The Mind-Melting Potion 

This one's different. When you drink it, you get an 8-second trip: your screen goes dark and erupts with spinning kaleidoscope patterns, fractal stars collapsing inward, geometric shapes folding toward center, and a hyperspace tunnel effect. After the trip, the regular rainbow overlay kicks in for the rest of the duration.

When someone brews a Mind-Melting potion, anyone nearby gets a chat warning

JEII

All items and potions show up in JEI with recipes and descriptions. Look them up there if you forget.