So what do you get with eight scaffoldings, two control rooms, a variety of water weaponry (preferably dyed), blindfolds with varying degrees of sabotage, and 85 people?
It'd be team versus team. There's one team captain for the Invaders and one team captain for the Towers. The Tower captain would pick eight Defenders, and the remaining 75 people would be the Invasion.
A path would be marked in some tactile way- maybe set of wooden boards running along it so the feet can feel it- and this would be the course the Invaders would run. (Or, more accurately, walk or perhaps shuffle carefully along.) This would therefore be a fixed-course game, especially since the scaffoldings- the towers- would already be in place.
There are all sorts of variations I can think of involving multiple waves and the Tower commander progressively getting more of the towers occupied, but the most basic form would be done in a single wave. Seperately from each other, without knowing of each others' plans (only of their resources), the Tower Coordinator decides who gets what weapon in what tower, and the Leader of the Invaders decides what order the invaders run in. They will, themselves, have grabbed random blindfolds, which allow for varying amounts of actual vision- and therefore, varying speed through the course. The Invasion Coordinator also has a few defensive supplies to give out: paper shields that will get soaked through after sufficient water (almost certainly demolished in one hit by a water balloon), large rain hats (headshots don't count), etc. (where by "etc." I mean "I don't have any more ideas right now"). Meanwhile, the Towers will be armed with small squirt guns and a bucket of water (easy to refill, hence a rapid fire rate, but not very wide), a bucket of water (only dumping permitted- but it can only be refilled by leaving the tower, so very slow fire rate), water balloons (limited ammo, replenishable only at the base of the tower, will go right through paper shields), a Super Soaker (can only be refilled at the base, uses water quickly), etc.
The Invaders score a point for everybody who makes it through dry. To play multiple rounds, trust people who are Invaders multple times to be honest about when they've gotten wet on the field.
This is a bad idea for all sorts of reasons, not the least of which involves the significant potential for severe personal injury (blindfolded people running through a mud-soaked course!), but it also seems like it would be an excellent time.
I was originally thinking of this in the context of the reality TV show "The Mole", actually, with 10 players (okay, nine players and one Mole) left in the game: one defense coordinator, one coordinator of the invaders, eight towers, and an exemption hidden among one of the piles of money stashed at the endpoint the 100 crew members acting as invaders will be taking away. And while it would undoubtably be awesome with reality TV production values (laser tag kits! played in the dark, and some invaders have no lights, so someone gets a spotlight tower!), I realized this might just be a better way for 85 people to get wet and waste an afternoon.