DROD is a game with an interesting gameplay, even if the game might not provide you hints about the action of it, you should know that playing it will force you getting through a lot of different and difficult puzzles that will put you to the test as you try to solve everything in order to reach the next level. Even if there are not too many levels in the game, all of them are really huge and it will take you a while in order to find out everything that is hidden inside all of the areas that you will have to travel through.
There are 25 levels in total, each of them being very large and besides this hugeness factor you will also be able to find secret rooms in which you can travel if you find a way to enter there. You might have to find a key, usually, but sometimes you are going to need other objects, too, in order to solve the puzzle of the door and get access inside. However, each room is worth the effort because you are going to find a lot of goodies inside that will help you get easier through the levels. There are weapons, shields and other interesting stuff inside.
The game might be one of the hardest that appeared in the puzzle genre, especially from amateur developers, but you should try to find a way to beat the game if you really want to become the DROD master. There are quite a few different enemies that you will have to avoid or defeat in order to get to the end and you will have to make good use of everything that appears in your way if you really want to reach the end of each of the 25 different levels.