User blog comment:LivesByProxy/Vision & Stealth Infographic 2017/@comment-7709681-20170912141417

I'm not fond that a character is vision-centric, but do agree that as one of the core goals/mechanics of a concept would be awesome.

Not only must be thought of how to make something unique or playful out of it, but how to make it fun and fair, and the only way to do that is through two steps:
 * 1) Design a medium of skill expression that is significant to play with and against, and being original enough to stand beside anything else in the process.
 * 2) Make the medium interact and synergyze with the rest of the tools at the concept's disposal without overwhelming, else you'll be forced to diminish the other tools' effectiveness.
 * 3) Measure its effectivity, as too much beneficial information leads to hard-counterplay (you'll be able to near-perfectly predict any of the opponents' movements, which render their decisions strategically insignificant.), and in that case the only means of balance available are:
 * 4) * Make it the only significant and/or appreciable element of the kit. This is done by diminishing the any other tool at the player's disposal and make them work towards complementing the mechanic, to the point that the concept has near to nothing else to offer to the game.
 * 5) * Gate it to the point that is too counterable by the opponent and too unreliable for your team. This is done by applying two or more of a plethora of conditions such as channeling, being out combat, requiring a unique resource, having a long cooldown, requiring another ally or ability, be done through another unit, that the opponent does a certain action, etc.
 * 6) * Nerf it or get rid of it.
 * 7) Ask yourself if it something that the player wants to do or face against, if the answer is "no" then isn't fun and should be re-designed.