Skull Carnival Slot by Zillion Games

A skeleton mariachi in a white suit and sombrero presides over a 5x4 grid set in a candlelit graveyard. The Boost symbol sums nearby bonus coin values into a single concentrated payout - three coins worth 8, 10, and 15 merge into one 33x hit. This value collection runs during both base game and Hold and Ring, where it also counts toward the 6-symbol trigger threshold.

Hold and Ring locks bonus coins in place while empty cells respin. The Mystery symbol can land during respins and transform into any jackpot coin except Grand - Minor, Major, or the mid-tier jackpot. These mystery transformations are the only source of jackpot coins during the bonus, so each one matters. Fill all 20 positions across the 5x4 grid and the Grand Jackpot (1000x) drops in.

Free Spins award 8 rounds triggered by 3 skull dice Scatters. Wilds become Walking Wilds that shift to random positions between spins, and landing 3 more Scatters retriggers with no upper limit. The Boost symbol participates during Free Spins for value collection but won't activate Hold and Ring from within the feature.