From Gundam to Decepticon Part 1: HG Murasame Build & Plan

Some Gunpla kits just ask to be customised. The HG Murasame is one of them.

With its sharp wings, jet-focused transformation, and aggressive silhouette, the Murasame already feels closer to a fighter aircraft than a traditional mobile suit. From the moment I finished the straight build, one idea kept coming back to me: Starscream. Not a direct Transformers copy, but a Gundam interpretation of that iconic Decepticon air commander.

This three-part series documents the journey from a stock HG Murasame to a fully realised Starscream-inspired custom. In this first entry, we’re starting where every good custom should: the straight build and the concept.

Why the HG Murasame Works as a Starscream Base

Starscream has always been defined by three things: air superiority, sharp angles, and attitude.

The HG Murasame checks all three boxes right out of the box. Its MA (mobile armour) mode is sleek and aggressive, with forward-swept wings and prominent thrusters. The silhouette already suggests speed and dominance, which makes it an ideal canvas for a Decepticon-inspired colour scheme.

Rather than heavy kitbashing, this project focuses on visual transformation with some structural modifications. The goal is to prove that colour, detail, and presentation can completely change the identity of a kit.

The Straight Build: Out of the Box

Before touching paint or decals, the kit was built completely stock.

The HG Murasame is a satisfying build with clean part separation and a surprisingly solid MA mode. The transformation feels intuitive and sturdy, which is important when planning a custom that will be handled and posed frequently.

Strengths noticed during the build:

• Excellent wing presence in MA mode
  

• Clean mechanical lines that will benefit from panel lining
  

• Strong central fuselage that reads well as a jet body

Limitations to work around:

• The stock colour scheme is very “Gundam”

• Some large white surfaces feel flat without added contrast

That flatness, however, is also an opportunity.

The first image shows the HG Murasame in MA mode, straight-built with no paint or decals. The white and black colour blocking is clean but neutral, and the red nose immediately draws the eye as the strongest accent. This image became the baseline for the entire custom plan.

As with Transformers, the HG Murasame’s ability to be taken from the MA mode to the Gunpla mode was a key reason for the customisation.

At this stage, the kit looks good but it doesn’t say anything yet.

Defining “Starscream” in Gunpla Form

Rather than copying Starscream exactly, this build aims to translate his visual language into Gundam terms.

Key Starscream traits being carried over:

• Light grey primary armour
  

• Bold red accents
  

• High-contrast secondary colours
  

• Clean, commanding presence rather than heavy battle damage

• Inversion of the wings in gunpla form

This isn’t a gritty, war-torn take. Starscream is arrogant, proud, and theatrical, and the finish needs to reflect that.

Colour Planning: From Gundam to Decepticon

The entire transformation hinges on colour.

The planned palette is deliberately simple:

• Light grey is the main armour colour
  

• Red for wings, nose, and key accents
  

• Black for mechanical depth and contrast
  

• Blue for thrusters and rear sections
  

• Gold/amber for cockpit and sensor highlights

By redistributing colour rather than adding complexity, the Murasame’s identity shifts dramatically without changing its shape.

The red wings dominate the silhouette, the blue thrusters add visual weight to the rear, and the Decepticon insignia subtly reinforces the theme without overpowering the design.

These photos served as the visual target during planning. Everything in this series builds toward achieving that look cleanly and intentionally.

What Will Change (and What Won’t)

What stays the same:

• MA mode proportions
  

• Transformation mechanics

What changes across the series:

• Full repaint

• Head, wing and cockpit modifications

• Panel lining and detail enhancement

• Decals and insignia

• Finish and presentation.

The Roadmap Ahead

This series is broken into three focused stages:

Blog 1 – Straight Build & Concept Planning

Establishing the base kit and visual direction (you are here)

Blog 2 – Recolour & Detail Work

Executing the Starscream palette and bringing the concept to life

Blog 3 – Finishing, Presentation & Final Comparison

Top coating, posing, and reflecting on the transformation

Each step builds on the last, showing how a standard HG kit can evolve into something completely different with patience and planning.

Final Thoughts

A straight build is never “just” a straight build. It’s the foundation of everything that follows.

The HG Murasame doesn’t need heavy modification to become something striking. Its form already tells a story, it just needs the right colours to change who that story belongs to.

In the next post, we’ll break the kit down, prep the parts, and begin the repaint that turns this Gundam into a Decepticon.

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