Uncle Leo

Uncle Leo is a friendly, wandering super mutant whom the Lone Wanderer can meet in a random encounter in 2277.

Background
Uncle Leo was exiled from his super mutant brethren because he was showing peace/dissent among his kind. Since then, he has roamed the Capital Wasteland. If asked about his name, he will reply "I... don't know. I guess I've always just called myself that."

Effects of player actions
When you first speak to Uncle Leo, he will express surprise that you haven't shot at him yet. When a dialogue option appears to tell him to give you his goods (essentially "robbing" him), he gladly imparts a suit of dirty pre-War businesswear to you as a gift, wishing he could give more.

Asking him what he meant when he said "before I became this" causes him to tell the player that super mutants are not born but are made by other super mutants in a cold, dark, metal place. He mentions that they use the captives that they take to make more of themselves, but he either doesn't know or cannot explain how this is done.

Uncle Leo can be encountered a second and third time. He will tell you that after your first encounter with him he fell into a dark cave while climbing a hill and hurt his leg. The cave turned out to be an old basement in which there were stacks of purified water. He tells you that after he got out of the basement he has been hunted by a group of "bleeders" (as super mutants refer to humans) and that he was forced to abandon the water he was carrying. As during the first encounter, he will offer you another suit of dirty pre-War businesswear. At the third meeting, the player can express their concern for Uncle Leo, believing the Wasteland to be too dangerous for him; given his previous run-in with humans. He will explain that if he allowed his own worries to get the better of him, he would never take another step. If you happen to have Fawkes as a companion while meeting Uncle Leo a second time, he will express his shock at seeing another super mutant like him.

Behind the scenes
"Ryokan, a Zen master, lived the simplest kind of life in a little hut at the foot of a mountain. One evening a thief visited the hut only to discover there was nothing to steal.  Ryokan returned and caught him. “You have come a long way to visit me,” he told the prowler, “and you should not return empty-handed. Please take my clothes as a gift.”  The thief was bewildered. He took the clothes and slunk away. Ryokan sat naked, watching the moon. “Poor fellow,” he mused, “I wish I could have given him this beautiful moon.”"
 * Uncle Leo's dialogue when you try to rob him, where he tells you the clothes are a gift and he wishes he could give you the "wonderful moon", comes from the following Zen Buddhist koan:

Tío Leo Дядя Лео