Play Bison Moon: Thunder Charge

Thunderstorms, bison and glowing moons make up the scenery in Bison Moon: Thunder Charge, a Northern Lights Gaming slot built around cash symbols and several connected bonus mechanics. The base game uses a 5x3 grid with 25 fixed paylines, while Red Moons can lead into the Stellar Moon Bonus, Moon Collector or Thunder Charge Bonus. We also get a Bison Stampede and a Lightning Eagle Jackpot feature. Apparently a quiet evening on the prairie wasn't on the design brief. 

The setting takes us into a North American wilderness under a dark, electrically charged sky. Mountains and open prairie sit behind the reels, while lightning and moonlight give the background most of the movement. The regular symbol set mixes bears, wolves, eagles and raccoons with card values, so the wildlife theme stays visible even before any feature begins. 

Among wildlife themed online slots, the presentation is more stormy than pastoral. Red and Blue Moon symbols stand out clearly against the darker background, while the bison imagery gives the game a clear visual identity. We also see flashes of light and stronger animation when feature symbols become active. The whole thing takes the usual majestic animal route, then adds enough thunder to make subtlety pack its bags. 

Card values occupy the lower end of the regular paytable, while the four animal symbols provide the larger potential line payouts. The bear sits at the top, followed by the wolf, eagle and raccoon. 

• Wild: The Bison Wild substitutes for regular paying symbols and appears in the base game only. 
• Red Moon: Red Moons appear in the base game and reveal cash prizes. Five can trigger the Stellar Moon Bonus, while six or more trigger the Thunder Charge Bonus. 
• Blue Moon: Blue Moons appear during the Thunder Charge Bonus and reveal cash prizes once their positions become available. 
• Key: Keys appear only during Thunder Charge. Two Keys unlock one of the initially locked rows, with another two needed for the second locked row. 
• Lightning Eagle: Lightning Eagle symbols feed the Lightning Eagle Bonus Meter. Collecting one on every reel triggers the Lightning Eagle Jackpot Wheel. 

Thunder Charge Bonus 

Six or more Red Moon symbols trigger Thunder Charge, and the cash prizes shown by those triggering Moons carry into the feature. Thunder Charge switches to a six row respin board, with rows 1 and 6 locked at the start and 3 respins available. A Blue Moon displaying the triggering cash prize remains held on the reels, except when Thunder Charge begins through the Jackpot Wheel. 

Unheld positions spin individually with Blue Moons, Keys and blanks. Any symbol landing resets the respin counter to 3. Each new Blue Moon also receives the current Bison Moon Cash Prize, and that prize increases each time another Blue Moon lands. 

Two Keys unlock row 1, while another two unlock row 6. Blue Moons landing in locked rows wait for their values to be revealed until the relevant row opens. Filling every position with Moon symbols unlocks all rows and produces the Grand Jackpot as a potential prize. 

Stellar Moon Bonus 

Exactly five Red Moon symbols trigger the Stellar Moon Bonus. Their displayed cash prizes are collected and then multiplied by a randomly selected value from x1, x2, x3, x4, x5, x10, x20, x50 or x100. The feature is compact compared with Thunder Charge, but the multiplier gives those five Moon values another route to a larger potential total. 

Moon Collector Bonus 

Red Moons can also activate the Moon Collector. Once triggered, the collector adds extra Moon symbols to the reels. Those additional symbols can help activate or strengthen either the Stellar Moon Bonus or Thunder Charge Bonus, so this mechanic works as a bridge between the two main Moon features rather than as a separate respin round. 

Bison Stampede 

A Bison Stampede can activate at the end of a base game spin. One outcome fills random reels with Wild symbols before any resulting potential line payouts are evaluated. The second places at least six Red Moon symbols onto random positions and sends the game directly into Thunder Charge. 

The Stampede appears only in the base game, giving the bison a practical job beyond looking suitably dramatic in the artwork. 

Lightning Eagle Jackpot 

Lightning Eagle symbols are collected through the bonus meter. Once an Eagle has been collected on all five reels, the Lightning Eagle Jackpot Wheel activates. 

The wheel contains two rows of outcomes, with each row potentially producing one of five jackpot prizes, a cash prize or the Thunder Charge Bonus. Potential cash prizes on the wheel are x5, x20, x50, x75 or x250. 

Charged Bet 

The Charged Bet places additional Red Moon symbols on the reels and multiplies the current stake by x2.5. Line payouts and Moon symbol values don't change because of this setting. The purpose is limited to increasing the number of Red Moon symbols available to trigger Thunder Charge. 

The base game runs on 5 reels and 3 rows with 25 fixed paylines. Regular symbols form potential payouts from left to right, while the Bison Wild can substitute for those standard symbols. Red Moons work outside the regular line paytable and carry cash values connected to the main bonus mechanics. 

Most of the mechanical variation begins when Moon symbols arrive in quantity. Five Red Moons can activate Stellar Moon, while six or more move the action into Thunder Charge and the respin system. The bonus board then introduces Blue Moons, locked rows and Keys, creating a different structure from the 5x3 base grid. Several other features feed back into those Moon mechanics, which gives the game more crossover between bonuses than a simple line slot. 

For related titles across online casinos, three previously reviewed games make sensible comparisons through wildlife themes, cash collection mechanics or feature driven bonus rounds. 

• Roaring Lions: Big Bass Jackpot Bonanza: The savannah setting and Money symbol collection make this a close comparison between animal themes and cash based bonus mechanics. 
• 5 Lions Megaways 2: Lion imagery keeps the wildlife connection strong, while the bonus structure gives the reels a busier mechanical side. 
• Kraken's Cove: The setting changes completely, but cash value collection and feature based payouts make this a useful mechanical comparison. 

Bison Moon: Thunder Charge has a lot going on, but most of the moving parts circle the same Moon system, which helps the game stay understandable. We particularly like how Thunder Charge develops as Keys unlock extra rows and new Blue Moons increase the Bison Moon Cash Prize. The Bison Stampede is another neat touch because the main animal actually does something besides stare nobly from promotional artwork. 

Our reservation is that six named features can make the rules look busier than the base game really feels. Once the connections between the Moon bonuses become clear, though, the structure is much easier to follow. We think the strongest appeal lies with those who enjoy wildlife themes, respins and cash symbol collection with several possible routes into the same central feature.