The Iron Colossus of Nuln
"The Iron Colossus of Nuln. All that is known is that it fell over onto an imperial regiment and squished it."
– Imperial Historian
This mod adds the Iron Colossus of Nuln to the Empire roster. It is a heavily armored mecha based on the Necrofex Colossus, with a tweaked animation set. This is save game compatible. 
The Iron Colossus is monster with a unit cap of just one. It is recruited only from the tier 5 Nuln Gunnery School and will also require an Imperial Academy in Nuln. It has stats based on the Necrofex Colossus, but with much higher armor, much slower, better melee, and reduced range on its cannon. There is an officer armed with a flamethrower on the mast who provides medium range supporting fire. The Iron Colossus can switch to a canister shot for short range combat.
The Iron Colossus has a couple unique abilities. The first is a passive called "Missile Magnet" that provides nearby friendly troops with the equivalent of a shield with 15 missile parry (works on all, so an unshielded unit gets 15 shield, and a unit with 30 shield gets buffed to 45), a 5% missile resistance buff, and +10 Morale. Ability range is 30 meters.
The second ability is called "Stand Back, She’s Gonna Blow" which is enabled at 10% health and gives you the option to destroy the Iron Colossus with the equivalent of a Skaven nuke explosion. The effect for this is why Belisarian’s vfx is required.
The Colossus will benefit from Lord skills and buffs for Steam Tanks, Great Cannons, and Demigryphs
Credits to:
Ole for the Asset Editor
Belisarian for the suggestion of the nuke effect and for checking every month that I’m not dead.
Venris for the original banner officers mod which I ended up using some banner textures from.
