We’ve all dreamed of knocking an army out quickly, and some of us may have even accomplished that. But what about getting an award-winning army done in only a single weekend? That’s what our very own Thomas Coltau achieved with this stunning Horus Heresy Mechanicum army!
He recently took this Mechanicum army to the Northern Highlights competition in northern Denmark and went home with two awards, one of which was a first-place trophy in the army category for these mean, green, Ad Mech machines. What’s even more impressive is that he painted this entire army in only three days. How did he achieve such an impressive feat? We lit the sacred incense, chanted the proper binaric, and anointed the holy cogitator with the blessed cant of awakening to consult with Arch-Magos Coltau himself to get the answers we sought.
Thomas: This is my Mechanicum army. There are many like it, but this one is mine!
For years, I’ve painted Imperial Knights in my custom household, Jotungard. I've always dreamed of creating an Adeptus Mechanicus force to match that colour scheme. When the Cerastus Knights were released, soon followed by the incredible plastic Mechanicum models for 30K, I fell in love. I knew then that the Horus Heresy setting was the perfect stage to bring my Jotungard vision to life.
I also enjoy challenging myself when painting army projects. Even though I’m not currently playing Horus Heresy, I love painting armies—it’s a completely different discipline compared to painting single display models. Army painting is as much about efficiency and smart shortcuts as it is about creativity and technique. The goal is to make models look great, fast.
In the past, we’ve painted entire armies for Bo over a weekend—even in a single evening—so I wanted to set a similar challenge for myself. Since I struggle to stay focused over longer periods without the motivation of gameplay, the time constraint became part of the challenge: could I paint an entire army over a weekend? With the right prep and some tried-and-true techniques, I believed I could.
Thomas: The first day was spent entirely on assembly (though I’ll admit—the Knight was already built!). I quickly discovered how complex these new Mechanicum kits are, with an impressive number of intricate parts.
By Friday night, I had everything built and primed. I used a black-and-white zenithal spray primer, topped off with a Matt Varnish to prep for airbrushing.
Thomas: In the morning, I began airbrushing. I’d tested colour schemes on paper earlier in the week, locking in the exact tones I wanted. I started with a pre-shade using Speedpaint Tyrian Navy, then built up the colour with Warpaints Air Angel Green. Highlights soon followed with Warpaints Air Greenskin, Cosmic Dust, and a light dusting of Pestilent Flesh to maintain depth and let the previous layers show through. I finished with a second pass of Cosmic Dust.
My favourite airbrush step came next: a coat of Speedpaint Ghillie Dew. It’s an intense, warm green that brings the whole scheme together. On top of the airbrushed gradients, it created a perfect, vivid finish. I then added a bit more Speedpaint Tyrian Navy in shadowed areas, mostly on the larger models.
Next, I sealed everything with Aegis Suit Satin Varnish Spray for two reasons: first, to prep for decals, and second, to create a semi-gloss surface ideal for washes. Varnishes are powerful tools for controlling how subsequent layers behave. After decals, I applied a thinned Warpaints Fanatic Dark Skin Shade across the models. The reddish-brown tone added the worn, weathered feel I was aiming for.
Then came another Matt Varnish. This dulled the decals, reducing their shine, but more importantly, it let me use one of my favourite speed techniques: applying Speedpaint over matt surfaces. This gives near-opaque coverage, perfect for fast army painting. I used Speedpaint Grim Black with my Wargamer Monster Brush on tracks, weapons, and other details. The upcoming weathering would hide any imperfections.
Next, I painted the dark metallic areas with Warpaints Fanatic Death Metal, followed by a Dark Skin Shade wash. In hindsight, this would’ve been quicker if done right after the satin varnish stage—one to remember for next time!
By Saturday evening, I left everything to dry and felt confident in the progress I’d made.
Thomas: I started the final day with sponge chipping using Warpaints Fanatic Brigandine Brown—a great way to simulate battle damage. I followed this with Warpaints Fanatic Effects Fresh Rust, used even more sparingly to create realistic rust streaks. These fine details help sell the illusion of a much more time-intensive paint job.
I gave the dark metallics an extra pass with a thinned Warpaints Fanatic Hydra Turquoise to boost contrast, then sponged Warpaints Fanatic Shining Silver highlights for edge wear. The bases were intentionally kept simple to keep focus on the models: textured basing painted with Warpaints Fanatic Dark Rust, then washed with Fresh Rust, and done.
Late Sunday evening, I was finally finished. It was incredibly satisfying to sit back and take in a fully painted army, completed in a weekend, to a standard I was proud of!
This project really shows how far you can go with a solid plan, some creative thinking, and smart use of tools and products. Even though I still haven’t played a game of Horus Heresy yet, I’m already looking to expand the army. I have a Heavy Support Detachment box on my desk—and another on the way—and I’m looking forward to painting even more of these amazing models… maybe with a bit more time next round.
