It’s been a senior year tradition — in some form — for years at high schools: Grade 12 students chasing and “eliminating” each other with water pistols for bragging rights.
It’s commonly called the “Senior Assassin” game and now there’s an app that collects video evidence and tracks the leader scoreboard.
Students taking part can be seen running around with goggles and pool floaties, which gives players immunity.
“We’ve been looking forward to it since the Grade 12 students played last year,” said Chloe Mackenzie, a senior at Sackville High School outside Halifax.
The game at Sackville High isn’t sanctioned by the school and there are strict rules where students have to play off school property.
The players themselves have imposed strict rules, too.
“We are very strict on the fact that if anybody’s caught taking somebody out on a video with like a real-looking gun (…) the person that has the real-looking gun is out,” she said.
Her older sister, Hilary Mackenzie, was a senior last year and has her own fond memories of the game.
“It was a lot of fun because we all run around school, chasing each other at lunchtime with the water guns trying to get each other out,” she said.
“And you’d see kids running out of the school to their cars at lunch so they could get into their cars so nobody could get them.”
Get daily National news
Get daily Canada news delivered to your inbox so you’ll never miss the day’s top stories.
But across the country, the game — and its popularity — is raising concerns for school officials and police.
Safety concerns
Police in Ontario have warned about the safety risks tied to the Senior Assassin game this week. In some cases, the students use Nerf-style or pellet guns to “eliminate” one another.
“Some of the imitation guns used in this game closely resemble real firearms,” said Supt. Bill Berg of the London Police Service Uniformed Division.
Earlier this week, Strathcona County RCMP in Alberta said they responded to a report of three youths believed to be pointing firearms out the window of a moving vehicle.
Police said it turned out to be water guns as part of the Senior Assassin game.
Last May, Strathmore High School in Alberta was placed under lockdown and a suspect was arrested when it appeared someone had shown up at the school with a firearm. That also turned out to be a water pistol.
A boy was arrested at gunpoint outside a Guelph, Ont., school last year, as well, because of the game.
“Strathcona County RCMP are reminding participants to be mindful of how their actions may be perceived by others. In particular, the use of toy or replica weapons in public spaces can cause alarm,” RCMP wrote Thursday.
“Interactions that may seem harmless among participants can be misinterpreted by others who are unaware of the game.”
Last moments of childhood
For Hilary, who is now a first year mathematics student at Acadia University, the game brings back good memories and she believes it deserves to be a tradition if played responsibly.
“It was one thing that my senior class actually did together. I know a lot of us didn’t get along all the time, but it was one thing we all got to have fun together and just laugh about it,” she said.
She has some words of wisdom for students playing the game this year, noting her classmates opted to use colourful dollar store water guns that were clearly toys.
“To the kids playing it, play with stuff that is obviously water guns. Don’t be spray painting it or change the color or anything,” she said.
“Make sure people can see that you are not a threat and that you’re just running around and having fun.”
The sisters’ mother, Deanne, has been a big supporter of the team-building game and issued a “public service announcement” on Facebook in an effort to make people aware of the game. She also acknowledged the activities can appear alarming.
“If you see teenagers hiding behind cars, lurking in bushes, sprinting through parking lots or acting wildly suspicious … don’t panic,” she wrote.
“They are enjoying the last moments of childhood,” she added.
© 2026 Global News, a division of Corus Entertainment Inc.