Needing some guidance...connecting 3 devices via wifi

Hi all, I'm new to the arduino developers community and am trying to figure out what direction to take for an upcoming project.

The project entails developing fake suitcase prop bombs for a paintball park. Each of the 3 props would feature an activation keypad that a user would need to specify to 'arm' the prop. Once each of the 3 props are armed, an audible ping sound would play over all 3 different props over the built in PA speakers.

My question is, how would I go about connecting these devices together wirelessly? Thanks!