brazen egret
The concept of making a player indefinitely invisible of course, has its upsides. I'm not here to say it's a terrible potion as it does its job and it does its job well. However, for such an overpowered effect, it's shockingly lenient. People under the effect can do whatev'z without consequence, and it's especially annoying when you have to brew the potions yourself, and some hooligan under the effect drains the pot as you add the ingredients.
I propose either one of two ideas:
Fix 1: Players under the invisible effect will remain invisible for as long as potion lasts, however, the effect is automatically disabled once they perform an action, be it attacking another player, activating a mechanism, or being affected by doohickeys such as springboards and hider detectors. This one's much more strict, but it would encourage players to use the effect for stealth, letting hiders hide and making seekers' surprise attacks feel more rewarding as you only have one true chance to strike.
Fix 2: Players under the invisible effect will cast a shadow depending on whichever body part happens to be touching a surface. Alternatively, it could cast a shadow directly under themselves at all times. Either way, it makes the act of being invisible a challenge for both sides, opaque or not. Those who are invisible need to be careful where they lounge around, making sure their shadow isn't too showy, and those who aren't need to keep an eye out for ominous circles appearing on the floor.
The goal of this nerfing is not to necessarily make being invisible a worse-off idea, but moreso to add a challenge to being invisible to compare with the other potions with drastic effects.
You can be invisible, but you can't be invincible.
slender charm
drifting zodiac
stiff elbow
silent estuary
alpine cloak
plush shadow