Entirely and utterly unneeded. In the wise words of Lulu
The Origin of orcs is written without made up stuff as you have done here with intricate roleplay that was involved throughout Aegis & Auslon.
First of all craotor one the first Orc's on the server already had four threads that outline what happened after Krug vanished. AKA the Clan War.
Secondly, you do not need to make up fictional sons of Krug that have nothing to do with Orcish RP for the past four years.
Krug had four legendary children out of all the rest, Rax, Dom, Lur, and Gorkil. Krug never used the title of Rex he was the Clan Father or the All-Father.
The Clan War was an extensive campaign between the four Mega Clan's at the time after absorbing the minor ones. The Clan War happened after the Legendry siblings died and their sons became Warlords of their respective clans.
Rax & Lur VS Dom & Gorkil fought for supremacy of Krugmar until Dom used Dark Shamanism which leads Gorkil the main force behind Dom's strength to leave the war altogether. Which cause the Dom to lose the war many legendary figures and Clan leaders died during the war.. Tythus was the Clan leader of Rax during that time when he won the war.
Tythus became King of Orcs, but he did not take the title of King instead, he used Rex which was to honor his clan the word Rex comes from Rax. Tythus honored the last Warlord of Dom who threw away the use of Dark Shaman's and fought honorably the title of Dominus was created from Dom.
Now lets talk about Krug; Jaxen is 100% correct Krug attacked Horen because he did not want to see Horen die in bed Horen was an ancient man when Krug struck the City of Oren. Furthermore, Krug and Horen before the war of Ibless were the closest of the four siblings. But here is the catch Krug fought Horen he defeated Horen in combat but did not kill him. Krug picked up Horen and walked into a Sandstorm both of them were never seen again and there is 0 reason to elaborate on what happened after they entered the storm mystery is good.