Ranked in these QuestionsQuestion Ranking
Pro Learn spells
There are magic scrolls that work once and rarer scrolls that let you learn the spell for the rest of the run.
Pro Can play for free
You can buy the premium currency, but you get enough of it through normal play that it's not required.
Pro Four character classes
One of them is a rogue, but you have to unlock it.
Pro Permanent upgrades
Each time you die or defeat a boss (every five floors) you get permanent upgrades, in the form of Runes (which you can swap out to customize your class at the start of each game) or Recipes (which you can use to craft items from materials found in-game).
Con Has ads
You can skip them with the premium currency. But the ads are always triggered by user action, so they don't randomly interrupt your games. This means they're also technically optional, but they give you bonuses you'll probably want.
Con Mediocre translation
While the basic spelling and grammar seem correct, the writing could really be better. It's often not clear what things do, even when they're documented.