Simple mod. Made with the polygonal lasso tool Krita. Still took around 3 hours. Looks bad? That's the point...

List of modified textures, data only mod:

./base/graphics/icons/ammo-category/artillery-shell.png
./base/graphics/icons/ammo-category/beam.png
./base/graphics/icons/ammo-category/bullet.png
./base/graphics/icons/ammo-category/cannon-shell.png
./base/graphics/icons/ammo-category/capsule.png
./base/graphics/icons/ammo-category/electric.png
./base/graphics/icons/ammo-category/flamethrower.png
./base/graphics/icons/ammo-category/grenade.png
./base/graphics/icons/ammo-category/land-mine.png
./base/graphics/icons/ammo-category/laser.png
./base/graphics/icons/ammo-category/rocket.png
./base/graphics/icons/ammo-category/shotgun-shell.png
./base/graphics/icons/artillery-shell.png
./base/graphics/icons/atomic-bomb.png
./base/graphics/icons/atomic-bomb-light.png
./base/graphics/icons/cannon-shell.png
./base/graphics/icons/combat-shotgun.png
./base/graphics/icons/explosive-cannon-shell.png
./base/graphics/icons/explosive-rocket.png
./base/graphics/icons/explosive-uranium-cannon-shell.png
./base/graphics/icons/firearm-magazine.png
./base/graphics/icons/flamethrower.png
./base/graphics/icons/flamethrower-ammo.png
./base/graphics/icons/flamethrower-turret.png
./base/graphics/icons/gun-turret.png
./base/graphics/icons/piercing-rounds-magazine.png
./base/graphics/icons/piercing-shotgun-shell.png
./base/graphics/icons/pistol.png
./base/graphics/icons/rocket.png
./base/graphics/icons/rocket-launcher.png
./base/graphics/icons/shotgun.png
./base/graphics/icons/shotgun-shell.png
./base/graphics/icons/signal/signal-weapon.png
./base/graphics/icons/submachine-gun.png
./base/graphics/icons/uranium-cannon-shell.png
./base/graphics/icons/uranium-rounds-magazine.png
./base/graphics/icons/uranium-rounds-magazine-light.png
./base/graphics/item-group/military.png
./base/graphics/technology/artillery.png
./base/graphics/technology/artillery-range.png
./base/graphics/technology/artillery-speed.png
./base/graphics/technology/atomic-bomb.png
./base/graphics/technology/destroyer.png
./base/graphics/technology/discharge-defense-equipment.png
./base/graphics/technology/distractor.png
./base/graphics/technology/explosive-rocketry.png
./base/graphics/technology/flamethrower.png
./base/graphics/technology/flammables.png
./base/graphics/technology/follower-robots.png
./base/graphics/technology/gun-turret.png
./base/graphics/technology/laser.png
./base/graphics/technology/laser-shooting-speed.png
./base/graphics/technology/laser-turret.png
./base/graphics/technology/laser-weapons-damage.png
./base/graphics/technology/military.png
./base/graphics/technology/personal-laser-defense-equipment.png
./base/graphics/technology/physical-projectile-damage-1.png
./base/graphics/technology/physical-projectile-damage-2.png
./base/graphics/technology/refined-flammables.png
./base/graphics/technology/rocketry.png
./base/graphics/technology/stronger-explosives-1.png
./base/graphics/technology/stronger-explosives-2.png
./base/graphics/technology/stronger-explosives-3.png
./base/graphics/technology/uranium-ammo.png
./base/graphics/technology/weapon-shooting-speed-1.png
./base/graphics/technology/weapon-shooting-speed-2.png
./base/graphics/technology/weapon-shooting-speed-3.png
./core/graphics/icons/mip/empty-ammo-slot.png
./core/graphics/icons/mip/empty-gun-slot.png
./space-age/graphics/icons/railgun.png
./space-age/graphics/icons/railgun-ammo.png
./space-age/graphics/icons/railgun-turret.png
./space-age/graphics/icons/teslagun.png
./space-age/graphics/technology/artillery-damage.png
./space-age/graphics/technology/electric-weapons-damage.png
./space-age/graphics/technology/railgun.png
./space-age/graphics/technology/railgun-damage.png
./space-age/graphics/technology/railgun-shooting-speed.png
./space-age/graphics/technology/tesla-weapons.png