Update for 2025!
You hear a noise... and spot something twinkling in the darkness... what is it? Another foe?
I've incorporated a version of these rules into our weekly Twitch streams... the tiles now have an image of "glowing eyes in the dark" on one side and the image of the monster (or fireburst trap, harmless rat, potion, scroll, or equipment) on the reverse side. Monsters still have a gold value attached inspired by the "bounties" given in the Japanese edition of HeroQuest.
The way I've used them now is that we play the game and viewers in the Twitch chat can use their 'Gold Coins' (channel points that build up over time watching, extra for followers and subscribers) to cash in a "Bonus Monster." When that happens instead of rolling a die and picking one from a list, I simply blindly fish a tile out of a big bag and place it somewhere out of LOS on the board. I move it up to 5 spaces on Zargon's turn.
When the "eyes" get adjacent (or diagonal close up) to a hero/ally, then I flip it over and place the miniature. If it happens to be a potion, scroll, or equipment, then I give that hero a random draw from those decks. Since the twitch chatter "really" wanted a monster though I will draw another tile and place it in another place out of LOS.
If the tile is revealed on Zargon's turn and it's a monster, that monster can attack (if any squares from that monster's fixed movement are left at that point they can also move that remaining amount before attacking).
And yes, if a Hero decides to shoot at the "glowing eyes" from a distance they can. This forces the tile to be revealed (if it's a potion, scroll, or equipment, then I say they destroyed whatever it was, oops! assuming they rolled any skulls; otherwise if they miss it's not revealed; I laugh at the idea of a potion rolling down the hallway or a scroll blowing in the wind). If it's "Vermin" then a harmless rat scurries away into the shadows, false alarm! There's also a blank tile, which is "just an illusion."
So far the tiles I've professionally printed are only of the GS monsters, in the distributions as if I had KK and ROTWL. I am working to get the other monsters done from the various expansions as well. Thanks to Bohemyus for the feedback and Sanswift for the playtesting that helped develop the idea further!
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