Once you figure out how to upgrade your heroes, customize your knights’ spells, spend gold and gems, and place puzzle pieces, Onion Knights is addicting. The Stage rounds (Easy and Hard) are short, so you can play a few rounds if you only have a small pocket of time for games. However, it’s easy to play round after round as you try to level yourself, earn enough gold for knight upgrades, and obtain the gems to buy more hero cards to upgrade your favorite hero, and progress far enough to beat the Hard Stage map. Gameplay is easy to understand but is more challenging as you progress through the map as Curry enemies get stronger and there are more waves to survive through — typical of the genre.