Casio has officially introduced Master in Horizon Gold, a three-watch G-Shock collection that gives the Gravitymaster, Mudmaster and Mudman the same brown and light-gold finish. The models are the GR-B300H-5A, GG-B100XMH-5A and GW-9500MH-5. They look related, but their functions are very different. One is made for flying, one for connected outdoor tracking and one for solar-powered navigation without a phone.

One Colour Scheme, Three Different G-Shocks

The collection takes its name from the line where the earth appears to meet the sky. Dark brown bio-based resin bands and cases are combined with light yellow-gold ion-plated bezels. Smaller metal parts use brown ion plating and the warm colour scheme looks unusual without hiding the tough Master of G character. Every model is shock resistant and rated to 200 metres.

Mudmaster GG-B100XMH-5A

The GG-B100XMH-5A measures 55.4 x 51.3 x 19.4 mm and weighs 104 g. Its bio-based carbon case uses the Carbon Core Guard structure, while a stainless-steel bezel and reinforced case back add protection. Mud resistance, mineral glass and a two-year CR2025 battery make it the only non-solar model in the trio.

The GG-B100XMH-5A is the connected Mudmaster in the collection. Image: Casio.

It combines a compass, altimeter, barometer and thermometer with a step counter. Bluetooth links it to the Casio Watches app for automatic time correction, around 300 world-time cities, Mission Log, Location Memory and phone finder. Other tools include sunrise and sunset data, a 1/100-second stopwatch, a 24-hour timer, five alarms and double LED lighting.

The stainless-steel bezel has a light yellow-gold ion-plated finish. Image: Casio.
Carbon Core Guard protects the GG-B100XMH-5A while keeping the structure rigid. Image: Casio.

Mudman GW-9500MH-5

The GW-9500MH-5 is thinner and lighter at 56.7 x 52.7 x 14.8 mm and 88 g. It has a bio-based carbon case, stainless-steel bezel, mud resistance and mineral glass. Its two-layer LCD keeps the compass graphics separate from the main time and sensor information.

The GW-9500MH-5 combines a full digital display with the shared brown and gold colours. Image: Casio.

This model replaces Bluetooth with Tough Solar and Multiband 6 radio time correction. Its triple sensor measures direction, altitude, barometric pressure and temperature. The watch also has 31 time zones, sunrise and sunset times, a 1/10-second stopwatch, five alarms and Super Illuminator. A full charge runs for about six months without light or 26 months with power saving.

The duplex LCD gives the digital compass its own graphic layer. Image: Casio.
The GW-9500MH-5 can show barometric pressure and temperature readings. Image: Casio.
Carbon Core Guard supports the Mudman’s shock-resistant and mud-resistant case. Image: Casio.

Gravitymaster GR-B300H-5A

The GR-B300H-5A is the largest by measurement but the lightest at 59 x 54.7 x 15.7 mm and 71 g. It uses Carbon Core Guard, a screw-lock crown, mineral glass and a bio-based resin band. Tough Solar powers the fully analogue display.

The GR-B300H-5A is the lightest and least expensive watch in the trio. Image: Casio.

Bluetooth provides automatic time correction, easy settings, around 300 world-time cities, flight log and phone finder. Dual time displays two cities together. The rotary disc at 9 o’clock shows alarm status, works with the stopwatch and indicates the battery level. A full charge provides about five months of normal use or 18 months with power saving.

The seamless case shape takes inspiration from modern aircraft. Image: Casio.
The carbon case helps the large Gravitymaster weigh only 71 g. Image: Casio.

Prices and My Choice

Confirmed Japanese prices are ¥60,500 for the GG-B100XMH-5A, ¥63,800 for the GW-9500MH-5 and ¥49,500 for the GR-B300H-5A. Recent exchange rates put them at roughly $370, €325 or £278 for the Mudmaster, $390, €342 or £293 for the Mudman and $303, €266 or £227 for the Gravitymaster. These are conversions rather than confirmed regional retail prices.

I already own a Gravitymaster, so the GR-B300H-5A is the watch that catches my attention first. It is also the lightest and least expensive model here. At 54.7 mm wide it is undeniably large, but an eight-inch wrist gives it enough room. The Mudman remains the practical choice for anyone who wants solar power, radio time correction and outdoor sensors without depending on a phone.