Seems that I managed to solve this. Here’s blueprint:
The idea is that each condition is ruled via bool value, an it adds either its intended value to the parameter, or 0 if bool is false.
I made a function that’s being fired every 0,2 seconds via delay node, doing what’s pictured and then triggering my other function that sets player’s visibility with gradual lerping in those same 0,2 seconds. That literal float will eventually be replaced with value derived from luminosity of the trace under the player, I hope, and then it’ll become fully functional system.