Thunder Skulls

"Don't ask if we are capable. Give us the mission!"

- A famous Thunder Skulls motto

The  are a mostly Codex Astartes-compliant Loyalist Chapter of Space Marines and a Successor Chapter of the Silver Skulls, itself supposedly a Successor Chapter of the Ultramarines of the Second Founding. It was founded in 974.M37 during the 23th "Sentinel" Founding following a vision witnessed by the Chief Prognosticator Aerus Vashiro of the Silver Skulls, who anticipated that the Segmentum Tempestus would soon face major problems and convinced Lord Commander Argentius to send the entire 5th Company to garrison the region preemptively as a new chapter with the permission of the High Lords of Terra.

The vision proved to be true as in 113.M38 the Black Crusade of Von Mallas errupted in the Segmentum Pacificus and soon spread to the Segmentus Tempestus. By the time that the Black Crusade came, the Thunder Skulls had already been dealing with local instability in the region for over a century and had established strong roots in the Santacruz sub-sector, where they are known to the locals as "Caveiras".

Notable Campaigns

 * Black Crusader of Von Mallas (113.M38 - 955.M39)

Chapter Homeworld
Ondina is located in the Catarina System of the Santacruz sub-sector, itself a part of the Ember Sector of the Segmentum Tempestus.

Chapter Chant
Loyalty, fearlessness, integrity!

Will be our motto!

Always ready to battle!

All enemies of Man!

Anytime, at any cost!

Thunder Skulls will claim victory!

With extreme prejudice!

We terminate our enemies!

Heretics, Xenos and Traitors!

We will defeat them all!

War without respite!

Loyal soldiers!

Thunder Skulls!

Our Chapter, fearless and strong!

Do not retreat!

We boldly face the enemy!

Victory, our promised glory!

For the Emperor!

Chapter Gene-Seed
The Silver Skulls remained ignorant as to the truth of their genetic heritage for most of their history. The name of their primogenitor was unknown to them as the records have been lost. However, some fragmentary references in Imperial records indicate that the Silver Skulls had been one of the more famed Chapters to have been formed during the Second Founding after the end of the Horus Heresy. The countless genetic tests on the Silver Skulls' gene-seed suggested that they were most likely a Successor Chapter of the Ultramarines and the great Primarch Roboute Guilliman. Though their Chapter colours, iconography and combat doctrine suggested that they had ties to the Iron Warriors Traitor Legion.

All questions of their ancestry were put to rest when the resurrected primarch Roboute Guilliman confirmed that they were indeed descedent from his gene-seed during the Indomitus Crusade. This revelation was of little significance to the Thunder Skulls chapter, as they had put little importance in their progenitor primarch to begin with. They were always more prideful of their parent chapter, the Silver Skulls, and their cultural heritage.

Notable Thunder Skulls

 * Lord Commander Florian Antenor: The original Chapter Master of the Thunder Skulls. He was the Captain of the Silver Skulls' 5th Company that were turned into the first Thunder Skulls during the Sentinel Founding. He was chosen by Lord Commander Argentius following the guidance of a vision from Chief Prognosticator Aerus Vashiro to found a new chapter with his 5th Company in the Segmentum Tempestus to thrawt a future threat to region.
 * Lord Commander Robert Peperit: The current Chapter Master of the Thunder Skulls. He was one of the original members of the Silver Skulls' 5th Company that were turned into the first Thunder Skulls during the Sentinel Founding. He was made the Captain of the 2nd Company of the Thunder Skulls at the chapter's founding and earned himself numerous honour during the Black Crusade and subsequent conflicts. This culminated with him assuming the role of Lord Commander before M41.
 * First Captain Octavius: The current captain of the elite 1st Company. He was one of the original members of the Silver Skulls' 5th Company that were turned into the first Thunder Skulls during the Sentinel Founding. Many thought him the successor of Lord Commander Antenor, but he was overshadowed by the then Captain of the 2nd Company, Robert Peperit, who became the new chapter master.
 * Captain Neto Gouveia: The current captain of the 2nd Battle Company. Neto is a native of Ondina and was recruited by the Thunder Skulls prior to the start of Von Mallas' Black Crusade. He is seen by many as the successor of Lord Commander Robert. He is the first Ondina native to reach the rank of captain of one of the Battle Companies.
 * Captain Fabius Barbarosa: The current captain of the 3rd Battle Company. He was one of the original members of the Silver Skulls' 5th Company that were turned into the first Thunder Skulls during the Sentinel Founding. He became known as Barbarosa for the red mask that he wears instead of a full helmet.
 * Captain Oliver: The current captain of the 4th Battle Company. He was one of the original members of the Silver Skulls' 5th Company that were turned into the first Thunder Skulls during the Sentinel Founding.
 * Captain André Mathias: The current captain of the 5th Battle Company. Mathias is a native of Ondina and was recruited by the Thunder Skulls prior to the start of Von Mallas' Black Crusade. When the conflict began he was serving as a Scout Marine in the 10th Company. During the Black Crusade he distinguished himself with his fearlessness and devotion to the chapter and earned himself a place in the 5th Company as a Tactical Marine. By the 41st Millennium he has become the commander of the company. He is a close friend to Lord Commander Robert.
 * Captain Tatius: The current captain of the 6th Reserve Company. He was one of the original members of the Silver Skulls' 5th Company that were turned into the first Thunder Skulls during the Sentinel Founding.
 * Captain Formoso: The current captain of the 7th Reserve Company. A native of Ondina.
 * Captain Renan: The current captain of the 8th Reserve Company. A native of Ondina.
 * Captain Paulo: The current captain of the 9th Reserve Company. A native of Ondina.
 * Scout Captain Rocha: The current captain of the 10th Scout Company. A native of Ondina.
 * Chief Prognosticator Rosarius: The current Chief Prognosticator of the Thunder Skulls Chapter. He was one of the original members of the Silver Skulls' 5th Company that were turned into the first Thunder Skulls during the Sentinel Founding. The most important decisions faced by the Chapter are ultimately handed over to the Prognosticatum and its governing council is overseen by Rosarius.
 * Chief Apothecary Petrus: The current Chief Apothecary of the Thunder Skulls Chapter. He was one of the original members of the Silver Skulls' 5th Company that were turned into the first Thunder Skulls during the Sentinel Founding.

Chapter Colours
The Thunder Skulls wear dark-gray Power Armour with the exception of the insets of the shoulder guards, which are black. Various details of the armor are painted a metallic silver in honour of their parent chapter, the Silver Skulls. These include the right kneepad, the aquila, the shoulder trims and part of the backpack.

The symbol on the right shoulder guard designates operational specialty: battleline, close support, fire support, Veteran or command. The colour of the squad specialty symbol indicates company number in accordance with the dictates of the Codex Astartes: i.e. White (1st Company), Yellow (2nd Company), Red (3rd Company), Green (4th Company), etc.

Squad allegiance is indicated on the right knee plate by a black High Gothic numeral stenciled on it. Squad sergeants paint their helmets with their company color, while lieutenants paint the helmet top and mask. This practice gives each company their respective nicknames (i.e.: 1st Company - Caveiras Brancas, 2nd Company - Caveiras Áureas, 3rd Company - Caveiras Rubras, 4th Company - Caveiras Verdes, 5th Company - Caveiras Negras, 6th Company - Caveiras Laranjas, 7th Company - Caveiras Roxas, 8th Company - Caveiras Cinzas, 9th Company - Caveiras Azuis).

Chapter Badge
The Thunder Skulls' Chapter badge is a stylized white skull, similar in appearance to the one used by the Silver Skulls, centered on a field of black. The skull is impaled on a silver blade with a yellow thunderbolt crossing the black from the top right towards the bottom left.