Gronk's Gems Slot by Hacksaw Gaming

Two separate bonus rounds with completely different rule sets split this game in half. Gronk's Treasure (110x to buy in) keeps the base game's charging mechanic intact across 10 free spins, while Gem Hoarder (200x) strips charging out entirely and replaces it with a progressive multiplier. Three Gronk's Head scatters open the first path. Three Gem Bag scatters open the second. They don't share mechanics at all.

The charging system is the base game's core loop. When a cluster wins on the 6x6 grid, that symbol type enters a charged state tracked by a bar above the reels. Charged status persists through every cascade in the spin, and multiple types charge simultaneously if different clusters win across separate cascade steps. Once cascades stop, the Epic Gem activates - it drops into gaps left by removed winning symbols, converts every remaining charged symbol to the highest-paying charged type, and absorbs them into one cluster. The gem itself counts as 4 symbols, so even a single leftover charged symbol plus the gem creates a 5-symbol cluster. A grid loaded with three charged types and 15 remaining symbols becomes a 19-symbol cluster of the premium type after transformation.

Gem Hoarder plays nothing like that. No charged symbols, no Epic Gem. Instead, a global multiplier grows by the exact number of symbols cleared in each cascade step - remove 8 symbols, it jumps by 8. The X-Gem wild only appears in this mode, and when a winning cluster touches one, the full global multiplier applies. Two X-Gems in the same cluster double it. Five refilling spins sounds tight, but landing 3 more Gem Bags resets all 5 and the multiplier carries over. A multiplier that's been climbing for 10+ refilled spins hitting a cluster connected to two X-Gems is where the math compounds.

The HIGH_4 gem symbol pays 1,500x for a 36+ cluster, which is the full grid. Individual clusters without Epic Gem conversion stay moderate on purpose - the paytable is built around that single transformation moment converting a screen of charged low-pays into the premium type.