Tomas' injuries were very grave. The burden that his body and, more importantly, his soul suffered when he fused with his Law Avatar was immense.
Not to mention that the energy in the Sage's attack had contaminated his body at a cellular level, which caused horrible mutations.
He consumed all the healing drugs that were at his disposal and then took the arduous journey through the elemental chaos, passed the Crystal Wall, and finally returned to the Beta Heavenly World.
The Angelic Paragon flew as fast as he could. He was afraid that his absence would put the Heavenly race in danger.
And he was right. The moment he was able to contact Oliver, he understood how grave the situation was.
Somehow the Magi invader force realized he was not in the world and they took that opportunity to extend their domain over the continent. They built two magic towers in the time he was away.
