Best Microgaming Slots to Play Online 

Mega Moolah is one of the world’s most iconic games, and in our demo testing it plays exactly the way its reputation suggests: safari-themed, 5 reels, 25 paylines, and unremarkable on the surface until the jackpot wheel kicks in. The base RTP is 88.12%; once you fold in the average return from the progressive jackpot pool, that climbs to about 93.42%. It’s rated low volatility, which tracked in our sessions: wins came often but stayed small outside of the jackpot.

Worth knowing: “Mega Moolah” now covers a small family of games with different math models, including the original, Mega Moolah Isis, 5 Reel Drive, and the newer WowPot network (launched by Games Global in 2020, and the source of some of the largest headline jackpots in the series, including a roughly €38.4 million win in early 2024). We’re covering the original, classic version here. Check the game title in the casino lobby carefully, since the variants aren’t identical.

Best For: Players who want low-volatility base gameplay with a shot at a life-changing jackpot

Break Da Bank is a genuine Microgaming classic, dating back to 2008. It’s a stripped-down 3-reel, 5-payline game with a bank-heist theme, wilds that multiply your win when they land, and a fixed top prize of 2,400 coins rather than a progressive jackpot. RTP sits at 95.75% with high volatility. In practice, that meant longer stretches without a win in our testing, offset by bigger payouts when the wild-heavy combinations landed.

One fact-check worth flagging: don’t confuse this with Break Da Bank Again, a separate, newer 5-reel, 9-payline sequel with its own RTP (95.43%) and a much higher max win (37,575x bet). Both are in circulation at Microgaming casinos, so check the exact title before you sit down.

Best For: Players who like the classic 3-reel mechanics without a lot of bonus complexity

Immortal Romance has held up remarkably well since its 2011 release. It runs on 5 reels and 243 ways to win, and its four separate free spins modes, each tied to a different character with its own multipliers and modifiers, are still the main draw. RTP is officially 96.86%, though it’s worth knowing that some casinos run lower-paying configurations (94.12% or 92.1%) of the same game, so it’s worth checking the in-game info screen before you commit real money.

High volatility means the win pattern is lumpy: expect a hit frequency around one in three spins, but with most of the meaningful money concentrated in the bonus rounds rather than spread evenly. The max win is 12,150x bet.

Best For: Players who enjoy deep bonus features and can tolerate dry spells between hits

Book of Oz, released in December 2018, is a much newer addition than Mega Moolah or Immortal Romance. Developed by Triple Edge Studios and distributed through Microgaming, it runs on 5 reels and 10 paylines, with an RTP of 96.50% when respins are in play (96.31% in the base configuration) and a 5,000x max win.

It’s a classic-style book slot: expanding symbols, scatters, and a respin feature that can extend a bonus round. Volatility is high, which is the part that matters most for anyone new to slots. Book of Oz is easy to understand, but its high volatility means beginners should test it in demo mode first and use small stakes if playing for real money.

Best For: Newer players who want simple mechanics, provided they start in demo mode given the high volatility

Thunderstruck II dates back to 2010 and remains one of Microgaming’s deepest games in terms of bonus variety. It runs on 5 reels and 243 ways to win, with four separate free spins modes tied to Norse gods, each carrying its own multipliers and modifiers. RTP is 96.65%.

Volatility ratings vary by source. We’d call it medium-to-high rather than strictly one or the other, since the base game pays more evenly than something like Immortal Romance, but the free spins modes can swing results considerably. Max win is 8,100x bet.

Best For: Players who want frequent, moderate-sized wins with multiple bonus modes to choose between