Graham McNeill
The Either

Tybalt Marr, Captain of the Sons of Horus, swears to bring down a thorn in the Warmaster's side: the commander of the so-called "Shattered Legions", the infamous Shadrak Meduson.
The Horus Heresy
short

Also in:
The Horus Heresy Audio Collection Volume 3
Shattered Legions