Coin Volcano bonus features: original vs sequel, UK edition
The UK rule that changes this whole comparison
Most bonus guides for these games spend paragraphs on Bonus Buy pricing — 30x or 50x for the standard round, 75x or 100x for Ultra Bonus, 300x for Coin Volcano 2’s Boost mode. If you play in Great Britain, skip all of it: feature-buy is not permitted on slots offered by UKGC-licensed operators, so none of those purchase options appear in a British lobby. The only way into any bonus round here is the natural trigger — three coin symbols on the central line. That makes trigger frequency, not buy price, the number worth caring about, and it is exactly what a demo session measures for free.
Which game’s bonus suits you
| You want | Better fit |
|---|---|
| The shortest path to understanding Hold and Win | Coin Volcano (3x3, 9 positions) |
| Longer rounds with more landing spots | Coin Volcano 2 (3x5, 15 positions) |
| The higher advertised ceiling | Coin Volcano (2,551x vs 500x) |
| More multiplier interaction per round | Coin Volcano 2 (guaranteed upgrades in Ultra Bonus) |
| A fifth jackpot tier to chase | Coin Volcano 2 |
How the shared Hold and Win core works
Both games run the same skeleton. Three qualifying coins on the highlighted central line move to the bonus grid and award three re-spins. Every new coin that lands in an empty position resets the counter to three. The round ends when re-spins run out or the grid fills — and filling it pays the Grand Jackpot on top of every collected coin value.
The supporting cast is identical in name, different in density:
- Sticky Coins lock onto the reels before the bonus starts and carry over into it, so a round can begin with more than three occupied positions.
- Mystery Symbols resolve at the end of the round into a coin, a Sticky Coin, a jackpot symbol or Coin Collect (which sums the visible prize symbols). Mystery Jackpot resolves only into Mini, Minor or Major.
- Volcano Multipliers are position upgrades: when the volcano erupts, one or more grid positions gain a multiplier, and any prize symbol sitting there is multiplied at settlement. A single position can be upgraded repeatedly within one round.
Where the two games diverge
Coin Volcano: 9 positions, four jackpots
The original resolves everything on a 3x3 bonus grid. Jackpot ladder: Mini 10x, Minor 20x, Major 50x, Grand 500x–2,500x (may vary by casino version) — the single biggest version difference in the series, and visible only in the lobby paytable. Nine positions mean short, decisive rounds: one or two dead re-spin cycles usually settle it.
Coin Volcano 2: 15 positions, five tiers, two extra modes
The sequel widens the bonus grid to 3x5 and adds a fifth jackpot tier, with the Grand fixed at 500x for filling all 15 positions. Its Ultra Bonus starts with guaranteed multiplier upgrades and more frequent eruptions. The Boost Bonus Game — eruptions upgrade positions by +5 instead of +1 — exists only behind Bonus Buy, which means UK players will simply never see it: an international-only mode in practice.
Side-by-side
| Parameter | Coin Volcano | Coin Volcano 2 |
|---|---|---|
| Bonus grid | 3x3 (9 positions) | 3x5 (15 positions) |
| Jackpot tiers | 4 (Mini/Minor/Major/Grand) | 5 |
| Grand Jackpot | 500x or 2,500x by version | 500x |
| Ultra Bonus | Yes | Yes, with guaranteed upgrades |
| Boost Bonus Game | No | Buy-only — absent in the UK |
| Advertised max win | 2,551x | 500x |
| Bonus Buy in UK lobbies | Not permitted | Not permitted |
| Round length feel | Short, decisive | Longer, more incremental |
A wider grid is not a better grid: 15 positions take longer to fill, so Coin Volcano 2 rounds build gradually where the original’s resolve fast. The maths of each game is set by its RTP model, not by position count.
Casino bonuses are a separate thing entirely
A welcome offer, deposit match or promotional free spins come from the operator, never from 3 Oaks. Before accepting one for these slots, check three lines of the terms: whether Coin Volcano contributes 100% to wagering, the maximum stake allowed while a bonus is active (often below the £5 cap), and the withdrawal conditions. UK operators cannot accept credit cards (banned since April 2020) and must offer deposit limits and GAMSTOP — treat missing tools as a licence red flag, not a cosmetic gap.
18+. Bonus rounds are entertainment, not income — set a budget before the first spin. BeGambleAware.org offers free, confidential support; GAMSTOP covers self-exclusion on all UK-licensed sites.