Kronos Slot Review: The Complete WMS Kronos Family

Every game covered here comes from WMS Gaming, the Chicago studio that is now part of Light and Wonder. Light and Wonder is the current owner of the WMS catalog and the company that licenses these titles to physical casinos and, through its iGaming platform, to legal online operators. Each Kronos title is a video slot dressed in an Ancient Greek theme, all marble columns, gold thrones and storm clouds gathered over Mount Othrys. The core hook rarely changes: reels crowded with the bearded Titan, a golden bonus symbol that unlocks free spins, and a lion wild that only lands on the center reels. What shifts from the original to Unleashed is the grid size, the number of paylines and the way the bonus round plays once it starts.

One clarification belongs at the top, because it is the single most common mix up in this family. Kronos and “Kronos Father of Zeus” are not two separate games with different math. “Father of Zeus” is the descriptive tagline WMS attached to the original 2013 Kronos, and many casino cabinets and online listings sell the same base game under that fuller name. The genuinely distinct sequel is Kronos Unleashed, released in 2018 with a new reel engine, a new bonus symbol and the Red-Hot Lightning Respins feature. This page treats the original and its “Father of Zeus” branding together, then breaks out Unleashed on its own, so the specs never get quoted interchangeably.

A second point of confusion is worth clearing up before the specs begin. Kronos sits alongside WMS’s better-known Zeus line, and the two share a mythology and a house style, which leads some players to treat them as one franchise. They are separate games with separate math, separate symbols and separate bonus rules. Zeus is its own title with its own free spins model, and nothing on this page about Kronos should be read as applying to Zeus. The two are cousins in theme only. When a lobby lists both, they are distinct machines, and the tagline “Father of Zeus” on the Kronos cabinet is a story reference, not a claim that the two games share an engine.

Quick-View Table: The Flagship Kronos

These headline numbers describe the original Kronos, the 2013 game that started the family, which is the title most players picture when they hear the name. Where the wider family swings sharply, the detail is broken out further down. Any figure WMS or Light and Wonder does not publish is marked so, rather than guessed.

Version Comparison Table

This table lines up every version named on this page. The original Kronos and its “Father of Zeus” branding share one set of specs, so they read alike; Kronos Unleashed is the genuine redesign. The max win for Unleashed is left as “Not published” because third-party sources disagree wildly and Light and Wonder has not published an official ceiling.

Game Overview and How It Plays

The original Kronos is a deliberately clean five-reel, three-row machine with 20 paylines. Its defining trait is that those lines pay in both directions, left to right and right to left, which effectively doubles the chances of a combination landing compared with a standard one-way slot. Coin values begin at 0.01 and climb to 3, and the common online build accepts stakes from about 0.20 up to roughly 60 per spin. The reels sit on a calm blue and gold backdrop above the clouds, and the presentation leans regal rather than frantic, a contrast to the storm-lashed sequel.

Symbols stack on the reels in the base game, which is the engine behind the biggest base-game hits: when the tall Kronos or throne icons drop in as a full stack, a single spin can paint multiple lines at once. The lion wild only appears on the three center reels, so it never anchors a win on its own from reel one, but it fills gaps in stacked combinations and is the symbol most likely to complete a big both-way line. The whole design is built to feel patient, then reward the free spins round, where extra wilds and additional stacked symbols are seeded onto the reels to lift the hit rate well above the base game.

The presentation of the original matches its patient math. The reels float on a serene above-the-clouds backdrop in blue and gold, the soundtrack is restrained until a win lands, and the whole cabinet is designed to feel stately rather than frantic. That calm is deliberate, because it sets up the contrast when the free spins begin and the reels fill with wilds and stacks. Players coming from louder modern slots sometimes read the base game as slow, but the pacing is the point: the original Kronos rewards the wait, and its best moments arrive in the bonus rather than spin to spin.

Kronos Unleashed keeps the mythology but throws out the compact grid. It plays across five reels and eight rows, a towering 5×8 matrix with 60 paylines in the base game, and during its signature respin the grid expands to 12 rows and 100 paylines. The published RTP is 95.86 percent and the volatility sits in the medium to high band. Where the original is a stacked-symbol slot with a straightforward free spins bonus, Unleashed is built around a hold-style respin mechanic with power-up symbols that can trigger jackpots, multipliers and further grid expansion. It is a louder, more modern game, with an animated Kronos looming over the reels and a cinematic orchestral score.

What Makes the Original Kronos Different

Two design choices define how the original Kronos feels, and both are easy to miss if you only glance at the pay table. The first is the both-way pay rule. Standard slots read winning combinations from the leftmost reel rightward, so a symbol has to appear on reel one to start a line. Kronos reads its 20 lines in both directions, which means a run of matching symbols that starts from the rightmost reel counts just as much as one that starts from the left. In practice this roughly doubles the ways a given screen can produce a win, and it is the reason the game hits more often than its compact 20-line grid would suggest. It also changes how the lion wild earns its keep, because the wild sitting on reel four can complete a right-to-left line even when the left side of the screen is bare.

The second defining choice is stacked symbols. In the base game the premium icons, the Titan and the throne especially, arrive as tall stacks that can fill an entire reel at once. When a full stack lands on a reel that already lines up with matching symbols elsewhere, a single spin can light several of the 20 both-way lines together, which is where the base game’s biggest hits come from without any bonus involved. This stacking behavior is also what the free spins round amplifies: by seeding extra wilds and extra stacked symbols onto the strips, the bonus turns an occasional base-game event into the default state, which is why a long free spins run is the moment the game is capable of its best sessions. Understanding these two mechanics matters more than memorizing a coin pay table, because together they explain both the medium-to-high volatility and the way the game rewards patience.

Symbols and What They Pay

The original Kronos runs a themed symbol set led by the Titan himself. The highest-paying icons are Kronos, the golden throne, the winged Pegasus, a ring and the peak of Olympus. Beneath them sit the familiar low-value card ranks, styled here as polished colored gemstones rather than plain letters so they blend into the marble-and-gold look. Because the game pays both ways, a run of three matching high symbols starting from either the left or the right edge counts as a win, which is why modest-looking screens can still register a payout.

WMS did not publish a single fixed coin pay table that survives across every operator, because the values scale with the coin denomination and the number of coins staked. As a rule the Kronos symbol and the throne are the premium payers, the Pegasus and ring sit in the middle, and the gemstone card ranks fill out the low end. The top line award on the original is worth in the region of 2,250 times the line stake, which is the figure to anchor expectations rather than any single coin number.

Bonus Symbol Cross-Check

The versions do not all use the same bonus symbol, so this is worth stating plainly rather than assuming the family shares one icon.

• Kronos and Kronos Father of Zeus (the same 2013 game): the bonus symbol is a gold medallion scatter. The wild is a lion that appears only on reels 2, 3 and 4.
• Kronos Unleashed (2018): the bonus symbol is a different design, a golden sun-style shield bearing a lion’s head, commonly described as the Sun scatter. It also carries a wild that lands on the center reels, but the scatter art and the feature it launches are not the same as the original.

The practical takeaway is that a player who knows the original’s gold medallion should not go hunting for the same picture in Unleashed. The trigger symbol changed with the sequel, and so did what happens when it lands.

How to Trigger the Bonus

On the original Kronos, the free spins round is triggered by landing 3 or more gold medallion scatters anywhere in view. The scatters do not need to sit on a payline. The count of scatters sets the size of the award: 3 medallions pay 10 free spins, 4 medallions pay 25 free spins and 5 medallions pay a generous 100 free spins. That 100-spin top award is one of the reasons the game built a loyal following, because a five-scatter hit sets up a long, wild-heavy bonus.

On Kronos Unleashed, the free spins round is triggered by landing 3 or more of the Sun scatter symbols. The sequel adds a wrinkle: once the scatters land, a feature determines exactly how many free spins are awarded rather than always paying a fixed number for the scatter count, so two triggers with the same number of scatters can hand out different spin totals. Unleashed also carries its Red-Hot Lightning Respins as a separate feature that is entered through special symbols rather than the scatter, which is covered in the next section.

How the Bonus Works

This is the section where the two engines split most clearly, so each is described on its own.

On the original Kronos, the bonus is a free spins round and nothing more elaborate. Once 10, 25 or 100 spins are awarded, the game reels spin automatically at the triggering stake, but the reels are enriched for the duration: extra lion wilds are added and additional stacked symbols are loaded onto the strips. That seeding is the whole point. In the base game the wild is confined to three reels and stacks are occasional; in the bonus, stacked high symbols and extra wilds arrive far more often, so full-screen or near-full-screen both-way wins become realistic. A 100-spin trigger with these enriched reels is where the game’s best sessions come from. There is no wheel, no pick round and no multiplier ladder; the value is in volume and density of wilds.

Kronos Unleashed plays its bonus very differently. Its headline feature is the Red-Hot Lightning Respins. When it starts the game grants a set of respins, typically beginning at three, and every time a qualifying power-up symbol lands the respin counter resets, in the same family of mechanics as a hold and win. The power-up symbols each do something distinct: a red lightning symbol can award one of the jackpots, a green cross symbol can apply a multiplier, purple arrow symbols expand the grid taller by adding rows, and a further symbol type spreads coverage across the reels. As the grid stretches from 8 rows toward 12 and the multipliers stack, the paylines climb from 60 to 100 and the win potential rises with them. The separate Sun-scatter free spins round layers additional free games on top. The result is a busier, more feature-driven bonus than the original’s clean free spins, aimed at players who prefer power-up collection to simple spin volume.

Version by Version

Kronos

The original Kronos launched in 2013 as a WMS Gaming cabinet and is the foundation of everything else on this page. It is a five-reel, three-row slot with 20 paylines that pay in both directions, and its published RTP sits between 95.94 percent and 96 percent depending on the source and the operator configuration, with volatility in the medium-to-high band. Coin values run from 0.01 to 3, and the online demo build commonly accepts stakes from about 0.20 up to 60 per spin. The reels are dominated by stacked symbols, so the base game can deliver sudden multi-line hits when the tall Kronos or throne icons fill a reel, and the lion wild, restricted to reels 2, 3 and 4, is the glue that completes those combinations.

The heart of the original is its free spins round, triggered by 3 or more gold medallion scatters for 10, 25 or 100 spins, with extra wilds and stacked symbols seeded into the reels for the duration. The top win is in the region of 2,250 times the stake, which by modern standards is modest, and Kronos should be understood as a game that pays through frequency of decent hits and long free spins runs rather than a single life-changing jackpot. In the United States this is fundamentally a land-based WMS title. Online demo versions circulate internationally, but at the time of writing its live presence in regulated US online lobbies could not be confirmed, so it is treated here as land-based for this market.

Kronos Father of Zeus

“Kronos Father of Zeus” is not a separate release with its own math. It is the original 2013 Kronos sold under the fuller tagline WMS used to market the game, a nod to the mythology in which Kronos fathered Zeus, Poseidon and Hades. Many physical cabinets and online listings display the game under this longer name, which is why players search for it as though it were a distinct title. Every specification matches the original: five reels, three rows, 20 both-way paylines, the gold medallion scatter, the center-reel lion wild, the 10, 25 or 100 free spins, an RTP around 95.94 percent to 96 percent and a top award near 2,250 times the stake.

Because it is mechanically identical to the original, there is no separate spec table for this entry; the flagship quick-view table above already describes it in full. The only thing that changes is the marquee on the machine. If you sit down at a cabinet badged “Kronos Father of Zeus” and one badged simply “Kronos,” you are playing the same game with the same reels and the same bonus. This version, like the original, is a land-based fixture in US casinos, with online demo builds seen internationally and no confirmed live presence in regulated US online lobbies at the time of writing.

Kronos Unleashed

Kronos Unleashed arrived in 2018 and is the true sequel, released under the Light and Wonder umbrella that now owns the WMS catalog. It abandons the compact three-row grid for a towering five-reel, eight-row layout with 60 paylines that expands to 12 rows and 100 paylines during its signature respin. The published RTP is 95.86 percent, slightly below the original, with volatility in the medium-to-high band. The betting range on the common build runs from about 0.20 to 50 per spin. Where the original leaned on stacked symbols and a clean free spins round, Unleashed is built around the Red-Hot Lightning Respins, a hold-style feature seeded with power-up symbols that award jackpots, apply multipliers and expand the grid, alongside a separate Sun-scatter free spins round triggered by 3 or more scatters.

The max win on Kronos Unleashed is the one spec that cannot be pinned down honestly. Third-party sources quote figures as far apart as 5,000 times the stake, 50,000 times and even 250,000 times, and Light and Wonder has not published an official ceiling, so this review marks it “Not published” rather than repeat a number that cannot be verified. What is certain is that the win potential is driven by the multiplier power-ups stacking during the respin, which is a different and generally higher-ceiling model than the original’s fixed free spins. In the United States, Unleashed is primarily a land-based cabinet. An online build exists and circulates in international demo form, but its live availability in regulated US online lobbies could not be confirmed at the time of writing, so it is presented here as land-based for this market rather than as a game you can currently load at a US operator.

Strategy and What to Expect

There is no way to influence the outcome of a Kronos spin, because a random number generator sets every result independently, but a few grounded expectations help you play the family sensibly. The original Kronos is a medium-to-high volatility game with a top award near 2,250 times the stake, which places it firmly in the category of slots that pay through moderate hits and free spins rather than a single huge jackpot. Sessions tend to grind through the base game, carried by the both-way lines and the occasional stacked-symbol screen, until a scatter trigger opens the free spins. Because the 5-scatter trigger pays 100 free spins on enriched reels, the whole game is effectively built around reaching that round, and bankroll planning should assume long stretches between meaningful hits.

Kronos Unleashed asks for a different mindset. Its win potential is concentrated in the Red-Hot Lightning Respins, where the value comes from power-up symbols stacking multipliers and expanding the grid rather than from raw spin volume. That makes the swings feel sharper: quiet spells while you wait for the respin to start, then a burst of activity when the power-ups begin resetting the counter. The published RTP of 95.86 percent is close enough to the original’s that neither game is a clearly better mathematical bet; the choice is about which bonus you prefer to chase. Whichever version you play, the smart approach is to set a stake you can sustain across many spins, treat the free spins or respin round as the goal, and walk away when the budget you set is spent. Our primer on reading a slot’s numbers before you commit is at /help/how-to-choose/.

Mobile Play

Both engines were built to run on phones as well as desktop, and the online demo builds of Kronos and Kronos Unleashed scale to portrait screens with the reels resized and the spin controls tucked along the bottom edge. The original’s compact three-row grid reads cleanly on a small display, while Unleashed’s eight-row tower needs a taller layout and benefits from a larger phone screen so the power-up symbols stay legible during the respin. If and when Kronos content appears in a regulated US app, it plays through the operator’s own casino app or mobile browser with no separate download for the game itself. Our guide to playing slots on a handset lives at /mobile/.

Where to Play

If your goal is to play WMS and Light and Wonder slots for real money in a regulated US lobby, start from our vetted operator list at /legal-sites/, which tracks which casinos are live in your state and what each one carries. Because the Kronos family is heavily land-based, it is also worth checking a casino’s search box for the exact title before you deposit, and reading up on how return figures work in our RTP guide and how swing is measured in our volatility guide. Players who enjoy the sequel’s harder edge can find similar titles grouped under high volatility slots, and anyone ready to move from demo to cash can compare deposit options through our real money hub.

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