A Fresh Start for the Monster

Maximum cushioning in running shoes usually comes with a trade-off. You get protection and comfort, but you sacrifice responsiveness and ground feel. The shoe becomes a recovery tool rather than a training partner—something you wear because you need to, not because you want to.

On's Cloudmonster series has spent the past few years challenging this assumption. The original, launched in 2022, introduced a bold proposition: substantial cushioning that still felt dynamic and engaging. It wasn't the softest shoe available, but it had character. The distinctive CloudTec® pods and aggressive rocker geometry created a ride that felt purposeful rather than passive.

Following feedback that the Cloudmonster 2's upper didn't quite match the original's secure fit, On has responded with their most comprehensive update yet. The Cloudmonster 3 features a completely redesigned upper, enhanced triple-layer CloudTec® system, and refined geometry throughout.

Does it deliver what you need from a daily trainer? The answer depends on your priorities—and on what these updates actually mean for real-world training.

The Triple-Layer CloudTec® System

Most running shoes use solid foam blocks that compress uniformly when you land, absorb impact, and rebound to varying degrees. It's proven technology that works reliably, but it often creates a somewhat passive ride experience.

CloudTec® takes a different approach. The midsole features hollow compression pods—visible channels carved into the foam that create individual units compressing independently through your stride. When you land, the pods collapse vertically, absorbing impact whilst maintaining lateral stability. During toe-off, they decompress and spring back, creating forward propulsion rather than simply returning to neutral.

The Cloudmonster 3 introduces triple-layer construction. Previous versions used dual-layer CloudTec®; this adds a third tier throughout the midsole. The additional layer changes how the foam behaves under load—more material compressing and rebounding means both greater impact absorption and more energetic toe-off.

Stack height sits at 35mm heel, 29mm forefoot—a 6mm drop. This places the shoe below the 40mm+ stacks found in many current max-cushion options like the Hoka Bondi or Asics Superblast 3, though it's still substantial. The midsole uses Helion™ foam throughout, On's proprietary EVA-based compound designed for durability and consistent rebound characteristics.

At 309g for men's UK 9, the Cloudmonster 3 sits on the heavier end of the max-cushion spectrum—weight that becomes noticeable during faster efforts. This reflects On's design priorities: durability and structure over minimal mass.

Rocker Geometry and Forward Roll

The Cloudmonster 3 features what On describes as an "enhanced rocker shape"—more pronounced heel rounding compared to previous versions, working with a nylon-blend Speedboard® embedded through the midsole.

The rocker is pronounced. The heel is noticeably rounded, encouraging quick transition from initial contact through midstance. The forefoot rocker continues through toe-off, helping maintain forward momentum particularly during longer efforts where fatigue can disrupt natural rhythm. The Speedboard® adds stiffness through the midfoot without the rigid characteristics of carbon plates, reducing energy loss whilst maintaining enough give to avoid harsh feel.

Whether you'll appreciate this depends significantly on your natural running mechanics. Heel strikers generally find pronounced rockers beneficial, as the geometry facilitates smooth transitions. Midfoot and forefoot strikers gain less advantage, as they're not fully utilising the rearfoot design.

The combination creates a ride that feels quite directed. This isn't a neutral, do-what-you-want shoe. The geometry encourages a specific stride pattern, which works brilliantly if it matches your natural mechanics and less well if you prefer shoes that simply cushion without guiding.

The Firmness Factor

Here's where the Cloudmonster 3 diverges significantly from typical max-cushion expectations: despite the substantial stack height and "maximum cushioning" marketing, this shoe runs noticeably firm.

The Helion™ foam is denser and firmer than the soft compounds found in competitors like the Hoka Bondi or Asics Superblast 3. This firmness provides stability despite the high stack, prevents the mushy sensation many runners dislike in ultra-soft shoes, and contributes to durability—firmer foams typically maintain properties over higher mileage.

The foam does soften somewhat with use—reviews note the ride becomes more forgiving after 50-100 miles of break-in. However, even fully broken in, the Cloudmonster 3 remains on the firmer end of the max-cushion spectrum.

This matters enormously for setting expectations. If you're expecting deep, sink-in cushioning, the Cloudmonster 3 will feel surprisingly firm. If you prefer a more responsive, controlled platform with substantial stack height, the firmness becomes an asset.

The firmness also affects performance across different paces. At slower recovery efforts, the foam requires more force to compress effectively. At moderate training paces—marathon pace through steady aerobic efforts—the foam compresses and rebounds noticeably, creating the dynamic ride On intends.

Upper Construction: A Complete Redesign

The Cloudmonster 3 brings a completely redesigned upper—addressing the fit feedback that defined much of the conversation around version 2. An engineered knit construction provides structure where needed whilst maintaining breathability. The material quality feels noticeably premium—substantial enough to provide support without the rough feel.

The fit represents a significant step forward. True to size for most runners, with secure heel and midfoot lockdown. The toe box offers adequate space for natural toe splay without feeling excessively roomy. The tongue features enhanced padding and sits more securely, though it's slightly short and can shift downward during runs.

The Cloudmonster 3 is available in both standard and wide widths, accommodating runners who need additional room through the midfoot and forefoot.

Performance Across Training Paces

The Cloudmonster 3's versatility becomes apparent across different training contexts. The shoe performs best within a specific pace range, with performance degrading outside those boundaries.

At easy recovery pace, the firmness is most apparent. The CloudTec® pods require considerable force to compress effectively, meaning at slower paces you're running on top of the foam rather than engaging with the cushioning system. Runners seeking maximum cushioning specifically for recovery runs will find softer alternatives more suitable.

Steady long runs represent the sweet spot. At marathon pace and moderate aerobic paces, the rocker geometry becomes effective, the CloudTec® pods compress and rebound noticeably, and the firmness provides stability rather than harshness. The shoe handles 15-20 mile efforts competently, with the forward-rolling geometry helping maintain rhythm when concentration fades.

Tempo efforts reveal the shoe's intended purpose. The Cloudmonster 3 handles moderately fast paces—marathon through half-marathon pace—though it's designed more for steady efforts than speed work. The 309g weight and firm platform are more noticeable at faster speeds.

Stability is surprisingly good despite the neutral categorisation. The wide base, firm midsole, and structured upper create a stable platform even at 35mm stack height.

Understanding the Cloudmonster Range

On offers two primary Cloudmonster 3 variants, each targeting different training priorities and performance needs.

The standard Cloudmonster 3 at £180 features triple-layer CloudTec® with dual-density Helion™ foam throughout. Weight: 295. Stack: 35mm/29mm. This is the versatile daily trainer designed for steady-pace work and long runs, offering substantial cushioning with a firmer, more controlled platform. The rocker geometry and Speedboard® work together to create forward momentum at moderate training paces.

The Cloudmonster 3 Hyper, launching 19th March at £210, introduces Helion HF super foam—a PEBA-based compound—in the top layer, creating a noticeably different ride. Weight: 253g. Stack: 45mm/39mm. This version is considerably lighter despite the increased stack height, more responsive, and better suited to faster training paces. The Helion HF provides genuine energy return that makes the shoe feel livelier across varied efforts, from easy runs through to tempo work.

For most runners, the choice centres on training priorities. If your weekly schedule regularly includes tempo runs, progression efforts, and workouts alongside steady mileage, the Hyper's additional £30 is justified by meaningful performance differences—lighter weight, more responsive foam, and better versatility across pace ranges. If you're primarily accumulating steady miles at moderate paces without significant speed work, the base model provides adequate performance at lower cost whilst maintaining the durability and rocker geometry that define the platform.

On will also release a LightSpray Cloudmonster 3 Hyper later in 2026, featuring robot-sprayed upper technology that reduces weight to approximately 205g—the lightest, most performance-focused option in the range with limited availability.

Ideal Runner Profile

The Cloudmonster 3 makes sense for runners building long run volume during marathon or half-marathon training blocks. If you're consistently logging 40-60 mile weeks with most mileage at moderate, steady paces, the shoe handles this workload competently. The protection over extended distances is genuine, whilst the rocker geometry helps maintain rhythm when fatigue sets in.

Runners who've found ultra-soft max-cushion shoes unstable or mushy will likely appreciate the firmer platform. You get substantial stack height without the disconnected sensation some runners dislike in very soft options. The shoe particularly suits runners who appreciate pronounced rocker geometry—heel strikers gain more advantage from the design than midfoot or forefoot strikers.

From a practical standpoint, runners wanting one versatile shoe for most daily training—easy runs, steady long runs, occasional moderately fast efforts—may find the Cloudmonster 3 fits this role adequately.

That said, the Cloudmonster 3 isn't for everyone. If you're seeking maximum softness for recovery runs, the Hoka Bondi, Nike Vomero, or Asics Superblast 3 offer plusher cushioning better suited to easy efforts. The 309g weight becomes noticeable during harder training sessions—runners regularly tackling tempo runs and intervals will benefit more from lighter, more aggressive options. And whilst many appreciate the pronounced rocker geometry, it won't suit runners preferring shoes that simply cushion without actively guiding stride mechanics.

Durability and Long-Term Value

At £180, evaluating value requires considering durability alongside performance.

On shoes historically demonstrate excellent durability. The firm Helion™ foam maintains properties over high mileage better than softer compounds. Independent reviews suggest expecting 500-600km from the Cloudmonster 3 before the foam loses significant responsiveness—considerably more than softer super trainers typically delivering 400-500km.

The improved upper construction addresses durability concerns from version 2. The engineered knit shows minimal wear even after significant mileage, and the secure fit prevents material breakdown that occurred previously.

From a value perspective, the calculation depends on how well the shoe's characteristics match your training needs. If the firm, rocker-forward ride suits your preferences and you'll genuinely use the shoe for bulk weekly mileage, the combination of adequate performance and genuine durability justifies the £180 investment.

What You're Actually Getting

The On Cloudmonster 3 represents a well-executed update that addresses previous concerns whilst refining the platform that made the original compelling. The triple-layer CloudTec® system provides genuine cushioning, the enhanced rocker geometry facilitates smooth transitions, and the rebuilt upper creates secure fit that was entirely absent in version 2.

This isn't the softest max-cushion shoe available, nor the lightest, nor the most versatile across pace ranges. It's a firm, structured, rocker-forward daily trainer that excels at steady-pace training and long runs whilst maintaining stability and durability over high mileage.

The Cloudmonster 3 represents a thoughtful approach to max-cushion training shoes—prioritising structure, durability, and rocker-assisted transitions over ultra-soft landings or minimal weight. The £180 price point is justified by genuine durability and thoughtful design updates. For runners whose training centres on building steady mileage with a shoe that lasts, it's a compelling option worth considering. 

Finding the Right Fit at Achilles Heel

At Achilles Heel on Great Western Road in Glasgow, we've watched On's evolution with interest. Their early shoes earned a reputation for firmness and structure—sometimes to a fault. The current range, including the Cloudmonster 3, shows how they've learned to balance genuine cushioning with the distinctive ride characteristics that define their brand.

The Cloudmonster 3 represents an interesting proposition in the max-cushion category. Rather than following the ultra-soft trend dominating this space, On has maintained their firmer, more structured approach whilst adding substantial stack height. It's a shoe with clear strengths—the rocker geometry works well for building long run volume, the firmness provides stability that many high-stack shoes lack, and the durability should outlast softer alternatives.

That said, it's not a shoe that suits everyone. The firmness, pronounced rocker, and weight create specific characteristics that work brilliantly for certain runners and training contexts, less well for others. We've found it particularly appealing for runners who've been disappointed by ultra-soft max-cushion shoes that feel unstable or disconnected. If you prefer controlled platforms with genuine ground feel despite substantial cushioning, the Cloudmonster 3 delivers this better than most alternatives.

The Cloudmonster 3 launches 5th March at our shop, with the Cloudmonster 3 Hyper following on 19th March. Come by and we'll help you determine which version—if either—genuinely suits your training needs and fits within your broader rotation.

 

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Visit Achilles Heel on Great Western Road for expert fitting and advice on whether the Cloudmonster 3 suits your training. We'll assess your foot structure, running mechanics, and training needs to ensure you leave with footwear that genuinely supports your goals.