Airsoft is a team game played out in woodland, old buildings or purpose-built arenas. Two sides, an objective, and a fair bit of crouching behind things while working out where everyone went. Tactical when you want it to be, chaotic when you do not.
You need nothing to start. Marshals brief you, hand out the markers and protective gear, and run the games. Total beginners and big groups are the bread and butter of the sport, so stag dos, birthdays and work days fit right in.
The sessions on adventuro come with the gear and the game scenarios sorted. Bring clothes you do not mind getting muddy and a reasonable amount of competitive spirit.
