Thelonius was born in a small town near Mikona. As his parents got brutally slain by bugbears while he was out to collect wood in the forests, he was given to an orphanage. A pilgrim monk named Morand took him under his guidance and they lived in the southern forests of T'Nanshi for a while, where he had his first training lessons in martial arts. When Morand died, Thelonius moved back to Mikona.
In his first days he met Vitus Woodman, a far travelled druid, and his friend Aldorn Green. With them he had the chance to travel the lands of M'Chek and further into the Woods of T'Nanshi. They provided him basic knowledge about nature and balance. After his two close friends never came back from a long journey they made alone, he was a bit aimless and started to focus on his martial arts training which often drove him away from any signs of civilization and he became more and more used to survive on his own.
Years later, he met Nein, a monk which had a big impact on Thelonius way of fighting. He became more pragmatic, looking for weakness to exploit. But after Nein and Thelonius departed, it was another experience of behing left behind alone. This was followed by a great emptiness and very hard physical training.
The lack of guidance ended when Thelonius finally met Brother Ahn of the Order of the Dragon. He became his Mentor and introduced him to the Order of the Dragon where Thelonius became a member.
In the years with Brother Ahn and the Order Thelonius seemed to have found rest at last. But this did not hold on. As Brother Ahn withdraw into the mountains of deglos, to seek a higher form of enlightment, Thelonius was in deep grief. As a result he started to travel a lot, searching something he lost, though he did not know what it was that he was looking for. His travels brought him to the depths of Deglos and the Underdark, even to other planes. When he came back, he had been changed. He seemed to be crueler, more silent and had lost nearly all sense of humor. He applied for the Dragonguard and was trained by trained by General Jimbo in the art of the shadow. Furthermore, following Guardsmaster Logani, he joined the church of The'ton.
Nearly at the same time Thelonius met an unexperienced sagemonk named Anomandaari. For some time Thelonius was his mentor, but Anomandaaris ability to learn was tremendous, so that after a while Thelonius saw him as equal and they travelled a lot together. Around this time Thelonius was introduced to a strange person, that he always refered to as 'Ath'. Ath was a traveller of the planes, mysterious and following his own goals. But somehow these three were very similar in their search for something, yet not knowing what it was, that each one was looking for.
As Anomandaari left the church of The'ton and withdraw into the underdark, Thelonius was in deep grief again, especially as Anomandaari was more like a brother to him, but because of his pledge to the Order of the Dragon, he had to see him as an enemy. Few times they met afterwards, but against all odds their bond did not break. Anyway Thelonius started again to train alone in the darkest and deepest places, as well as the highest peaks of the Deglosian Mountains.
After decades of intense training, Thelonius ran into a man, that turned out to be his long lost friend Aldorn Green. While still seeing him as one of his longest friends, the gap between the two of them had become very large. The years of trying to reach his physical and mental limitations had turned Thelonius into a - on the first sight - coldhearted man. Though the fact, that he sees other beings very abstract and often lacks the ability to understand the feelings and needs of them, his absolute loyality to his few friends, to the Order of the Dragon and the Dreadlord The'ton is still undiminished.