Limbo is the simplest originals game: you pick a target multiplier and the game draws a random number. If the drawn number is higher than your target you win the stake times the target; if lower, you lose.
Why it is a relative of dice
Mathematically limbo and dice are the same game in a different shell. In both you choose the win chance yourself and in both the house edge is usually 1%, i.e. an RTP of 99%. The difference is only in the interface.
The choice of volatility is entirely yours
A target of 1.10× wins almost every round and adds a little. A target of 1000× wins once in a thousand rounds. The expected value is identical in both cases — what differs is only how long the balance lasts and how large a share of the result comes from a single hit. See volatility.
The auto-mode trap
A limbo round lasts an instant and in auto mode hundreds of rounds run per minute. At a high target that means the budget disappears before a hit has time to come. Set a loss cap before you start — the loss limit calculator helps find the number.
Verifiability
Like the other originals games, limbo is provably fair — the result can be recalculated yourself after the round.
Calculating the win chance
The win chance is roughly 0.99 divided by the target multiplier. A 2× target wins about 49.5% of rounds, 10× about 9.9%, 100× about 0.99% and 1000× about 0.099%, that is once in 1010 rounds. The product of the multiplier and the win chance is always 0.99, which is exactly the 1% house edge. So a higher target is not "worth more", only rarer.
Example: how long a dry spell can be
Take a 20× target. The win chance is 0.99 / 20 = 4.95%. On average a win comes roughly every 20 rounds, but that does not mean it comes after exactly 20 rounds. The probability that no win comes in 50 rounds in a row is 0.9505 to the power of 50 ≈ 7.9%. So roughly one 50-round stretch in 13 passes without a single hit, and that is perfectly normal. If your balance covers 20 stakes, that is very short. The higher the target, the bigger the bankroll you need; see volatility.
What to check
- Maximum multiplier and maximum payout. A game may cap the win of one round, so a very high target may not pay the stated amount.
- Auto mode. See the page on auto cashout; the same idea applies here: set the stop conditions beforehand, not afterwards.
- Result and seeds. Limbo is provably fair, but verify the seeds yourself, as the server seed and client seed pages describe.
The mathematical background is easier to follow with Wikipedia: House edge. Casinos that offer provably fair games are in the provably fair casino list. The general concept of volatility is explained in the freespin.ee glossary.