Many maps and games feature "invisibility" of units as a single special effect. You either are invisible or not, which is why it makes a big difference and is not suitable for the mass. The counter "revelation" is a likewise sharp-balanced effect. Now, I work on a hero defense containing big waves of enemy foes. You may know from Enfo's Team Survival e.g. that you can buy the Sentry Ward item in shop but you only need it in very rare situations because few enemies are invisible. However, it would be somehow annoying if invisibles were just mixed up and the player has no clue. I would like to ask/discuss for ways to include invisibility on a more regular basis but keep the controlling and information level to players high. idea 1: Rather than a permanent passive ability, invisibility is given through active buff spells like the one from human sorceress. This would decrease the accumulation and the player would see the casting in order to be less surprised. One would see more of an action that leads to the result. idea 2: Invisibles are not really unseeable the whole time but only non-targetable. The player obtains more information by effects or images which the hidden units spawn periodically at their position. Could be somewhat confusing. idea 3: There are different levels of invisibility that get automatically revealed when the units enter certain ranges of player characters. That would get rid of the annoying popping up/vanishing again of enemies when they strike you and add more gradualness. Well, of course, a particular high level could still grant full invisibility that is only discovered by special tools like the Sentry Ward.