
20+ years in the gambling industry including 13+ years playing and reviewing slots.
When a slot studio/provider creates a slot that is popular with players, a sequel will inevitably follow. Certain slot games become so popular that several sequels are released to create an slot game series.
Slot game series are either based around a theme (i.e. Age of the Gods), a certain slot game’s character (i.e. Gonzo’s Quest) or a jackpot network.
With some UK slot sites creating dedicated sections in their casino lobbies, slot games in the same series will offer different mechanics, new characters, higher win potential, differing volatility levels and new bonus features. In OLBG’s comprehensive guide, we delve into the best slot game series from the top slot providers. Enjoy!
Big Bass Slots
When Pragmatic Play released the Big Bass Bonanza slot back in December 2020, I’m sure they didn’t anticipate a whole Big Bass slot series with over 20 games. Spawning a whole host of fishing-themed slots from other providers, Big Bass slots are subject of various welcome bonuses including no wagering free spins offers.
Colourful, fun and easy to play, Big Bass slot games are amongst the most popular online. With new games released regularly, the series has taken the waters by storm with everyone’s favourite fisherman going on a new adventure with each game. Pack your fishing gear and get ready to hook in plenty of prize catches with the most popular slot series online.
Big Bass Amazon Xtreme is my favourite with 10,000 x bet max wins & a 4.3/5 rating.

Ultimate Guide to Big Bass Bonanza Slots
Age of the Gods Slots
Real-Time Ultimate Power Jackpot is £293,827.25
When Disney acquired Marvel, Playtech had to discontinue its range of Marvel slots. To replace them, they created the Age of the Gods slot series. Since Age of the Gods: King of Olympus was released in June 2016, there are now over 30 Age of the Gods slot games featuring various ancient Greek gods and mythical creatures including Zeus, Athena, Poseidon, Hercules, Midas and Apollo.
With excellent imagery and bonus features, all Age of the Gods series slots give you the chance to win 4 progressive jackpots. Triggered randomly on any base game spin, you need to match 3 gold coins to win the corresponding jackpot. The Ultimate Power Jackpot pays an average £499,000 every 44 days and has paid out a maximum €984,763 in October 2011.
Finally, Playtech enhanced the series further by releasing Norse mythology-themed slots in their Age of the Gods Norse slots. They come with 3 progressive jackpots (Ultimate, Daily and Instant) as well as exciting bonus features, different mechanics and Norse gods such as Odin, Freya, Loki and Thor.
My favourite is the Age of the Gods slot which offers 4 free spins features and 50,000 x bet max wins.

The Ultimate Guide to Age of the Gods Slots
Mega Moolah Slots
Back in November 2006, Microgaming (now Games Global) released the Mega Moolah jackpot slot. Becoming the most popular of all progressive jackpot slots, Games Global developed the Mega Moolah jackpot network which started with Atlantean Treasures Mega Moolah in February 2020.
There are now over 20 Mega Moolah slots all offering you the chance to win 4 progressive jackpots. Randomly won from any spin, you spin the infamous jackpot wheel to land on 1 of the 4 jackpots. The most desirable is the Mega Jackpot which guarantees at least £/€/$ 2 million.
The Mega Moolah slot series has paid out over €600 million with an average Mega Jackpot of €6.69 million every 49 days. With 20% of winners coming from the UK, Absolootly Mad Mega Moolah paid out a whopping €19.4 million in April 2021. Games Global has even added the Mega Moolah jackpots to popular slot games including Immortal Romance and Thunderstruck 2.
Immortal Romance Mega Moolah is my favourite as it offers the same gameplay as the iconic game with 4 jackpots thrown in.

The Best Mega Moolah Slots & Slot Sites
Rainbow Riches Slots
The iconic Rainbow Riches slot was released in May 2009 and has become one if not the most popular online slot games in the UK. Available online as well as in arcades and land-based casinos, Barcrest (now under the Light & Wonder umbrella) has been releasing leprechaun-inspired games ever since.
With over 20 games in the Rainbow Riches slot series, they all have an Irish luck theme and feature the most famous leprechaun on the internet. Offering different mechanics including Megaways and Cluster Pays, these light-hearted slots are fun and pay up to 12,500 times your total bet per spin.
With new Rainbow Riches slots released every year, there is even a dedicated Rainbow Riches Casino which was founded in 2019.
The original game may only offer 500 x bet max wins but it has a certain charm that is unrivalled.

🌈 The Best Rainbow Riches Slot Games: Compared
Monopoly Slots
With the Monopoly board game becoming the best-selling board game of all time, various slot providers including Gamesys, Light & Wonder, as well as Big Time Gaming, have released Monopoly-themed slot games.
The Monopoly slot series is pretty extensive featuring various themes, mechanics and bonus features. My favourite is Big Time Gaming’s Monopoly Megaways which has up to 117,649 ways to win, Reactions for continuous wins and a Free Spins feature with various extras awarded when Mr. Monopoly moves around the iconic board (such as max Megaways, extra free spins and win multiplier increases). It also boasts a high 96.5% RTP rate and offers 14,700 times bet max wins.
As with Rainbow Riches, there is a dedicated casino to Monopoly slots called Monopoly Casino.
All Monopoly slots feature the iconic board with many titles incorporating the board into bonus features.

Best Monopoly Slots & Slot Sites in the UK
Fishin’ Frenzy Slots
Blueprint Gaming released the original Fishin’ Frenzy slot game in September 2014. Simple and available in arcades and land-based casinos, Blueprint has created over 10 games in the Fishin’ Frenzy slot series which include various mechanics (such as Megaways) and bonus features.
Particularly popular in the UK, several Fishin’ Frenzy slots offer 50,000 times bet max wins. Due to their popularity, Blueprint Gaming offers local progressive jackpot versions called Jackpot King. Offering 6 and 7-figure jackpots, Blueprint has extended its Jackpot King network to other popular slots including King Kong Cash and The Goonies Return.
Fishin' Frenzy Megaways would be my pick as it stays true to the original game yet offer 50,000 x bet max wins.

The Ultimate Guide to Fishin’ Frenzy Slots
Fluffy Favourites Slots
When slot provider Eyecon released the Fluffy Favourites slot game in September 2016, little did they know they would create many more in the Fluffy Favourites slot series.
Popular amongst UK players, these cutesy, cheerful and colourful games are simple yet have the potential for big payouts. With a minimum max win of 2,500 times your total bet, Eyecon has expanded the series which sees games take place in outer space and using the popular Megaways mechanic.
Like the Fishin’ Frenzy series, Fluffy Favourites slot games also come with local progressive jackpot equivalents with 6-figures jackpots up for grabs.
My favourite game from the series is Fluffy Favourites Megaways which comes with 29,217 x bet max wins.

Complete Guide to Fluffy Favourites Slots
Money Train Slots
Created by Relax Gaming, they released the Money Train slot game in August 2019. It was only when they released Money Train 2 in September 2020 that the Money Train slots took off. With a third and fourth installment, each game offers more bandits and special symbols in the Money Cart Bonus feature as well as higher max win potential.
With the last game in the series, Money Train 4, you can win up to 150,000 times your total bet. Relax also created a progressive jackpot version which is part of their Dream Drop series.
Hugely popular, they all come with Bonus Buy features which lets you jump straight into the action. With Bonus Buys banned in the UK, Relax Gaming cleverly released Money Cart slots which offer just the Money Cart Bonus feature but with higher RTP rates and lower max win potential. The Money Train slots have proved so popular that there is even a Sling Money Train game.
The Money Train slots are amongst the most popular amongst players due to their thrilling gameplay, fast-paced action and high max win potential.

The Ultimate Guide to the Money Train Slots Series
Wilde Slots
Studio Play ‘n GO released Aztec Idols in December 2013 but Rich Wilde slots become popular when Book of Dead was released in January 2016. The series has expanded to include Rich’s daughter Cat and crazy uncle Gerard for a fully-fledged Wilde slot series.
With over 15 games available, you get to release your inner Indiana Jones and visit exotic locations around the world including ancient Egypt, the South American jungle, the lost city of Atlantis and the spiritual hills of India. Most Wilde slots use a ‘Book of’ mechanic in the free spins but there are several bonus features and mechanics to enjoy.
Whilst Book of Dead is by far the most popular game in the Wilde slot series, there are several gems in there including Pearls of India, Aztec Idols and Wildest Gambit.

Ultimate Guide to the Wilde Slot Series (Play'n GO)
Reactoonz Slots
Created by Play 'n GO, the first game to be released was Energoonz in 2013. Nearly 4 years later, Reactoonz came which then lead to a fully-fledged Reactoonz slot series.
Based on quirky alien creatures, you are taken on various interstellar adventures where you'll experience electrifying visuals, lots of bonus features and big win potential using the Cluster Pays mechanic. All games in the series interlink with the alien creatures featuring in all titles. There are new additions along the way including their creator (Dr Richard Toonz) and the leader of the pack (Gargantoon).
With Reactoonz becoming one of the most played grid slots of all time, the other games in the series as quirky, fun and unique.

Complete Guide to Play ‘n GO’s Reactoonz Slot Series
Dream Drop Slots
Real-Time Mega Jackpot is £2,424,628.59
Created by Relax Gaming in May 2022, the Dream Drop jackpot slot series has grown to over 40 games. With popular Relax Gaming slots having Dream Drop/jackpot versions, they all offer the chance to win 5 progressive jackpots. The Mega Jackpot is the biggest and pays up to €3 million every 1.5 months on average.
With so many games to choose from, Relax Gaming has partnered with Unibet Casino to release several exclusive Dream Drop and non-jackpot games. In our dedicated guide, you'll also find a list of all Mega Jackpot winners.
With Relax Gaming making Dream Drop versions of their most popular slot games, the network has grown substiantially. Other studios also offer Dream Drop slots.

Dream Drop Jackpot Slots Guide & Winners
WowPot Slots
Real-Time WowPot Jackpot is £2,424,628.59
Games Global (Microgaming) is famous for its Mega Moolah jackpot slots. However, they released the Wheel of Wishes WowPot slot game in February 2020. With 4 progressive jackpots on offer, Games Global expanded the WowPot jackpot series with 10 games at the time of writing.
Using different themes, bonus features and mechanics, the WowPot slot series is about progressive jackpots. Randomly won from any base game or free spin, the WowPot jackpot pays a minimum of £/€/$ 2 million. With over €225 million paid out to over 5.3 million winners, a jackpot was won every 15 seconds on average in 2023.
Wheel of Wishes WowPot is responsible for the world’s largest-ever progressive jackpot: a whopping €38.4 million!

Guide to WowPot Slots & Slot Sites
Watch this Space!
OLBG’s slots team will be creating more slot series guides in future. They include guides dedicated to:
- NetEnt’s Gonzo character
- ELK Studios’ Nitropolis series
- Playtech’s Kingdoms Rise series