PORTAL OVERLOAD cover art

PORTAL OVERLOAD slot: RTP and max win

By XIAOCHUN. Released 5 Oct 2026, math version 3.
Medium volatilityNo. 3035 most played this month

PORTAL OVERLOAD is a medium-volatility slot by XIAOCHUN on Stake Engine, released 5 Oct 2026. Its base game returns 96.50%, above the median Engine slot (96.02%) and higher than 66% of them. The top payout is 25,000× the bet, bigger than 81% of Engine slots; from a base spin it lands about once every 4,551,081 spins. It has 4 bonus buys priced at 60× to 300× the bet; the best returns 96.50%, so each buy costs 2.10× the bet on average over the long run. It is the No. 3035 most played Engine slot over the last 30 days.

Base RTP
96.50%
catalogue figure 96.500%
Max win
25,000×
of the base bet
Max win, base spins
1 in 4,551,081
25,000× top payout per spin
Base spin pays nothing
56.8%
of spins
Players, last 30 days
168
$11K wagered (Engine Insights)

Every mode, side by side

Costs are multiples of the base bet. Odds come from the published outcome table for v3. "Returns the cost" counts rounds that pay back at least what the mode cost. Expected cost is cost × (1 − RTP): the average amount lost per round over the long run.

ModeTypeCostRTPMax winMax win oddsPays anythingReturns the costExpected cost per round
BaseBase spin1.00×96.50%25,000×1 in 4,551,0811 in 2.311 in 4.950.04× base Simulate
AnteBoosted spin3.00×96.50%25,000×1 in 4,585,8941 in 1.911 in 6.630.11× base Simulate
BonusBonus buy60×96.50%25,000×1 in 4,469,8731 in 1.111 in 3.572.10× base Simulate
Feature Spin2Bonus buy100×96.50%25,000×1 in 4,774,4551 in 1.481 in 3.223.50× base Simulate
SuperBonus buy150×96.50%25,000×1 in 4,335,4231 in 1.081 in 3.525.25× base Simulate
HiddenBonus buy300×96.50%25,000×1 in 3,694,7541 in 1.061 in 3.4210.50× base Simulate

Work out the cost of PORTAL OVERLOAD bonus buys at your bet size

Version history

Base-mode RTP per published math version. Older versions stay public in the fairness API, so changes can be checked.

VersionBase RTP
v396.500%Active
v196.700%

Frequently asked

What is the RTP of PORTAL OVERLOAD?

Base spins return 96.50% of the amount wagered over the long run, from the published outcome table for version 3. All 4 of its bonus buys return 96.50%.

What is the max win in PORTAL OVERLOAD and how likely is it?

The top payout is 25,000× the base bet. On a base spin it lands 1 in 4,551,081 spins. In the Bonus buy (60×) 25,000× lands 1 in 4,469,873 buys.

Does PORTAL OVERLOAD have a bonus buy, and what does it cost?

Yes, 4 buy modes. Bonus: 60× the base bet, 96.50% RTP, an expected cost of 2.10× the base bet per buy. Feature Spin2: 100× the base bet, 96.50% RTP, an expected cost of 3.50× the base bet per buy. Super: 150× the base bet, 96.50% RTP, an expected cost of 5.25× the base bet per buy. Hidden: 300× the base bet, 96.50% RTP, an expected cost of 10.50× the base bet per buy.

Is PORTAL OVERLOAD high or low volatility?

Medium. Its base-mode standard deviation is 15.3× the bet, which puts it in the middle third of Engine games. What volatility means.

Can I check that a result was fair?

Yes. Engine games use provably fair seeds. Once your server seed is revealed you can replay any round against the published outcome table. See how to verify a result.

Slots with similar math to PORTAL OVERLOAD

Matched on volatility, max win, RTP and whether there's a bonus buy. Not on theme.

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