This game is delightful; a single super simple gameplay mechanic of "What order do you upgrade things" produces a crazy amount of variation and player control over outcomes. It's responsive in the sense that the player's actions have meaningful, significant influence on outcomes, intuitive in the sense that it takes a matter of a few seconds to learn the controls, and it has that certain something called "flavor." Everything about it is *simple* but *delightful*, from the graphics to the game mechanics to the soundtrack.

And it's a simple game, but *especially* for a game with a single primary player input mechanism, (Click to Upgrade), and just a handful of foundational mechanics (Darkness creep, adjacency bonuses, proximity-based upgrade rules), it has a ton of replay value!