I'm not going to be able to get through this review without mentioning Spelunky. It's inevitable. And it's not an unfair comparison.
I mean, they both resurrect retro genres (platformers in Spelunky, Metroidvanias in Rogue Legacy), but with randomly generated level layouts, and punishing perma-death whenever you kick the bucket.
But there's a key difference. While you start every Spelunky run with the same stats, Rogue Legacy lets you level up, and use money to boost your abilities, unlock skills, and buy weapons.
So in every run, you start with a little more power than before.
It means that in Derek Yu's platformer, you may eventually hone your skills to the point where you can finish the game. Maybe. But in Legacy, you will inevitably win because you'll simply become powerful enough to stomp on everything in your path.
It's a subtle design tweak, but it has a cataclysmic effect. In Spelunky, you feel like you're truly mastering the game, like you would an instrument. In Rogue Legacy it can feel like you're bopping down artificial barriers in a tedious war of grind and attrition.
In a lesser game, that could kill the whole thing from the off. But Rogue Legacy is fun and smart enough to make it work.
For one thing, your hero is always changing, both as you try new classes and as you deal with genetic quirks that range from the silly - nostalgics see the world in sepia - to the serious - those with Alzheimer's can't update the map, and the short-sighted peer through a fuzzy blur.
These new heroes are ostensibly your children - hence, the Legacy bit of Rogue Legacy - but I don't think Cellar Door makes full use of this clever idea. You never feel like your kids inherit your genes, just your swords and helmets.
It's also perilously addictive. The promise of one day being able to kill any enemy in a single sword swipe is a potent drug, and knowing that every run is propelling you forward means each attempt feels eminently worthwhile.
The castle is well forged, too. The algorithm never spits out crap layouts, and each fortress is filled with secret areas and unexpected enemies. You might stumble upon a whole new wing of the castle, or come across a massive boss.
Then there's the important fact that playing Rogue Legacy is just pure fun. The combat is crunchy, enemies are varied, and your hero is nimble and bouncy. The game has a sharp arcade sensibility, and knockabout low-gravity brawls.
It's not just about levelling up, of course. You also learn how to play better, how to control your hero, which spells to pick, which special moves to equip, each enemy's tells, and each trap's patterns. You master the game, in a small way.
And you can't simply grind out a cash pile. In the smartest design choice in the game, a castle gatekeeper confiscates any unused funds before you start your next run so hugely expensive upgrades must be earned in a single, heroic, tense, all-out adventure.
It's these clever touches that elevate Rogue Legacy, and save it from the missteps of its grindy gameplay loop.
Because while any one Rogue Legacy run can feel like getting a tiny, inconsequential foothold on your climb up a mountain, that run is - at the very least - frantic, slapstick, unpredictable, and unbelievably good fun.