NATCHEZ — William Hinson works as a plumber, and he was looking at a busted sewer line when he caught something unexpected — a Rhyhorn.

A Rhyhorn isn’t something foul coming out of a dirty pipe or some kind of sewer-dwelling creature, though, in a way, it is a creature. It’s a Pokemon.

Hinson, 26, is an avid player of Pokémon GO, a mobile phone app that launched this month and has taken off around the country. The Miss-Lou is no exception, and obsessive players can be seen around Natchez holding their phones up, seeking to “catch ‘em all.”

“I play it mostly when I get off work, but I check it periodically throughout the day,” Hinson said.

The game, which functions as an “augmented reality” that captures the real world on the screen of the players’ devices but also interjects virtual creatures, requires players to physically travel to different locations to capture different Pokémon in the augmented reality.

Game users can also train and battle the creatures they capture with other players.

In addition to playing in Natchez, Hinson has captured Pokémon in Fayette, Jonesville, around the lakes in Concordia Parish and Jackson.

Most of those Pokémon were captured by taking advantage of the change in scenery while he was traveling for other purposes, Hinson said, “but sometimes I travel just to see what else I can find, to see if something new pops up.”

Because the game uses real geography to place Pokémon — as well as PokéStops, which give players items they need, and Pokémon gyms, where users can battle their Pokémon — sometimes the Pokémon are difficult to access.

Quapaw Canoe Company operator Adam Elliott was coming in off the Mississippi River one day recently when he saw three kids standing around the boat ramp at Natchez Under-the-Hill.

“I joked around and asked if they were playing Pokemon, and they said, ‘Yeah, it’s difficult to catch some of the water-based Pokémon,’” Elliott said.

After thinking about the experience, Elliott pushed the idea of starting a Pokémon canoeing tour on Facebook. Nobody has taken him up on the offer, he said, but if the craze can drum up a little business, that’s all the better.

“I figured why not, people want to catch Pokémon, and they’re out getting a little extra exercise, they’re out of the way of cars and not falling off of cliffs, and if they fall in the water, they have a life jacket.”

One of the most popular Pokémon GO destinations in Natchez is the bluff, which has a designated gym area for players to battle their catches. Many of those playing, like Robert Williams, are in their late 20s and early 30s, and played the original Pokémon video and card games that were released in the mid-1990s.

But now that they’re working adults — Williams works at the nearby Steampunk Coffee roasters — playing has to take a backseat to employment, which means game time comes early in the day or after dark.

“If I play in the morning, I do it before the city is really beat down by the sun,” Williams said.

“At the peak excitement, after the release we were out there one evening and there were something like 50 people on the bluff, playing Pokémon at 10 p.m. After the sun goes down most evenings, there will be about 20 people out there.”

And those crowds of people are doing more than just playing a game together, Hinson said. It’s simply serving as a new social lubricant.

“With this new game, I see more people; it is more interacting and meeting of new people,” he said. “We hang out and have good times. Our little team usually has a group chat and meets up at the bluff, and we bring food and extension cords so we can plug up our phones so they don’t die, and we all work together. We catch Pokémon, but we also chit chat and joke around.”

And when the night grows old and phone battery life starts to run short, they can put aside the PokéBalls and head home, waiting to see what battles the next day will bring and what pocket monster they will catch when the sun goes down again.