His weapon of choice:

The leaky red water gun.

His backpack holds two more.

If he sees his target at long range, his Super Soaker is readily available in the passenger seat.

Senior Ryan O’Toole is one of 193 seniors participating in Senior Assassins.

“It makes it really hard to focus on doing homework because you’re always looking over your shoulder,” he said. “I do it even when I’m at home because I don’t trust my siblings. They could let somebody in the house and I wouldn’t even know.”

Senior Makila Hennig organized this year’s game by creating a Facebook group to get the word out. She then asked for any seniors who were interested to contact her. She assigned each person to a target.

“I tried to match people up with people they know,” she said. “I want them to at least know each other to make sure they can have fun, and it is not some random person they don’t know.”

O’Toole said the game preoccupies his mind.

He failed to complete his homework for a week because his focus was on strategies for the game.

O’Toole devises his exact exit from work each day. He first rolls a die to randomize his route. He then does a quick sweep of the area before he leaves. He carries his water gun at all times.

“I can’t assume that anybody around me is any more trustworthy than I am,” he said. “I would sell my own mother for a Klondike bar, much less to win the game.”

O’Toole said he would assassinate one of his friends without hesitation. He plans to use his connections to draw his target out into the open, then shoot him or her to take the target out of the game.

“Have you ever seen the look on a dog’s face when it’s realized that everything it’s ever wanted it can’t have because it doesn’t have thumbs to open the pantry?” he said. “That’s the best part — when you shoot somebody and they’ve got that look. It’s the look of absolute devastation on their face when they realize everything they’ve worked for is gone.”

The buy-in for the game was $1. This money goes into a pot for the winner and runner-up.

Although not a school-sanctioned event, this is one of the last activities for the seniors during their high school career.

“I’d like to win,” O’Toole said. “High school is done for me. I haven’t had time to go to any of the basketball games or soccer games this year, so this is really all I’ve got left for my senior year in high school.”