Marvin always wanted to have a powerful Advanced Shapechange skill, he was now able to have one with this Origin Leaf.
The other two Origin Leaves were still in the Migratory Bird Council's hands. They didn't give them to Marvin, but Old Ent used his reputation to vouch for them, which was definitely worth no less than an Origin Leaf.
Since that was the case, Marvin no longer thought about it.
Compared to these valuable treasures, the words of Old Ent were the biggest reason behind his decision.
"If even you, Mister Marvin, are reluctant to go to the Crimson Wasteland because of how terrifying it is, then how many people in Feinan would be willing to go?"
"What I am saying is, the Crimson Wasteland is really a very frightening place, but that is only for those who lack sufficient strength, am I wrong?"
These were clearly words of praise from Old Ent.
But Marvin also realized: He was afraid of the Crimson Wasteland because of its rumors.