Question 1

How accurate is the luck calculation?

Accepted Answer

The simulator uses the Slime RNG luck model for additives and multipliers, then applies binomial probability math for AFK forecasts. Adjusting buffs updates odds, expected rolls, ETA, and probability forecasts in real time.

Question 2

Does Rebirth Luck stack with Potions?

Accepted Answer

Yes. Rebirth provides a multiplier based on 1.82 raised to your rebirth level, and that multiplier compounds with potions, auras, gamepass luck, event luck, passive multipliers, and index percentage bonuses.

Question 3

What is the best way to get Celestial slimes?

Accepted Answer

Stack a high-tier aura with a strong luck potion, keep group and like bonuses enabled, raise rebirth level, and increase rolls per minute. The simulator shows which combination gives the best practical ETA for your target slime.

Question 4

Why does my ETA say Days?

Accepted Answer

Rare slimes can have base odds in the millions or higher. If your current total luck and roll speed are still low relative to that target, the expected time can correctly show hours, days, or longer.

Question 5

What is Gamepass Luck and is it worth buying?

Accepted Answer

Gamepass Luck is modeled as a permanent multiplier up to 3x. It compounds with temporary buffs, so it is most valuable for players who roll often or plan to push mid-game and endgame targets.

Question 6

How does the Index Bonus work?

Accepted Answer

The simulator separates index rewards into flat luck and percentage multiplier effects. Flat index luck is added to base luck first, while index percentage bonuses multiply the final additive total with other multipliers.

Question 7

Can I share my setup with friends?

Accepted Answer

Yes. Use Share Build to copy an encoded simulator URL containing your current parameters and target slime. Opening that URL restores the same setup automatically.

Question 8

What is the difference between Additives and Multipliers?

Accepted Answer

Additives such as base luck, group bonus, like bonus, friend bonus, zone luck, and index flat luck are added first. Multipliers such as rebirth, potion, aura, passive, gamepass, event, and index percentage bonuses then multiply that additive sum.

Luck Simulator

Configure your build first

Inverted Hoppity

AFK Forecast (Probability)

How to Use Simulator

Select Target

Apply Buffs

Check Odds

AFK Planning

Math Glossary

Additives

Multipliers

ETA

AFK Forecast

Simulator FAQ