Geishi Tenson is Taikoubou and the 12 Senins's teacher as well as the supreme master of Kongrong Mountain. Don't think that just because he looks old, he is weak. This winy old fox has much up his sleeve. He is supposedly the person who thought up the Houshin project. Geishi Tenson is also a very secretive person with much to hide. He lied to Taikoubou about the real purpose of the Houshin Project several times and is always seen trying to conjure up something (e.g. In Hon & In Cho incident). But overall, this old man is not only strong and wise, he loves his disciples dearly (especially Taikoubou) and he loves his home (Kunrun).
He is one of the 3 Great Sennins, the other 2 being Tsuotenkyoushu and Taijouroukun (Roushi). It was said at the beginning of the story that Genshi Tenson was the one who thought up the Houshin Project plan to stop Dakki. Actually, the motives of the Houshin Project changed several times in the Hoshin Engi timeline. First, it was only meant to destroy Dakki to save Ningenkai (human world), then it was to create a new dynasty, then it was to enclose Dakki's soul to save Senninkai (God's world), then it changed to destroying Jyoka. So yeah, Geishi Tenson is a difficult man to comprehend but to be honest, he does care a lot about Taikoubou (being his favourite student and all), but I'm not sure of his emotions towards Ou Eki (his past favourite student).
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Tier: High 7-A
Name: Genshi Tenson
Origins: Hoshin Engi
Age: Unknown, very old
Classification: Sennin Grandmaster, One of the great 3 Sennin
Lifting Strength: Class M+ via power-scaling
Striking Strength: Large Mountain Class via power-scaling
Durability: Small Island level via power-scaling
Stamina: Extremely high (Is constantly supplying the Houshi Dai, which is one of his Paopei that contains all of the Doushi and Sennin souls with energy, also never showed any signs of fatigue when using his Super Paopei Bankohan or when fighting Bunchuu)
Standard Equipment: His Super Paopei Bankohan
Intelligence: Genshi Tenson is very intelligent (Very knowledgeable in science and is an efficient leader and fighter). Additionally he is one of the highest accomplished Sennin, has hundreds maybe even thousands of years worth of fighting and general paopei experience.
Weaknesses: None notable.