What's up the "Future Generations" achievement? I've never come across that egg and I don't see it in the Monsternomicon
Spoiler
There is a space next to the Dragon, randomly chosen from the 8 adjacent spaces, that contains an egg. It registers as a 0, so you have to get kind of lucky to isolate it from regular blanks near the dragon, that or you just avoid breaking 0s near the dragon entirely. If you break it, you can get a free 3 exp, but if you preserve it to the end, you get the achievement.
There is a way to make it less random if you’re just going for the Future Generations achievement
Spoiler
Leave the squares around the dragon unclicked unless you know for certain they contain a monster. When you get the blue orb scroll, don’t use it. Save it for close to the end and if it has nowhere else to proc, it will reveal the squares around the dragon.
It’s not a slamdunk with the three stamp attempt, because you likely won’t have enough hearts to clear the board unless you’re very careful about only spending hearts on unrevealed monsters (vs the slimes that get revealed by the slime mage scroll).
I found the best strat for the three stamp run is to restart the game (you can just press R for a quick reset) until you get a favorable starting reveal. Ideally you want the mice to limit the search area for the rat king to no more than 3 columns or, ideally, indicate the exact column it’s in. Otherwise it’s almost impossible not to accidentally click on unrevealed mice as you work your way through the board.