Sound is vital in this game and can help the player move forward as well as provide hints to the situation Mary has found herself in. It is important to pay attention to dialogue and to your surroundings in order to proceed. In the game you are able to interact with items and NPCs.
The game's average playtime ranges from fifteen to twenty-five minutes to reach one ending, and there are four endings. It does contain horror elements, though they might never be encountered by a player who chooses to indulge in the dreams instead of investigating. Despite these influences, Dreaming Mary is not exactly a horror game.
It is inspired by the Japanese horror game Ib and the abstract game Yume Nikki, and is influenced by the indie platformer Eversion as well as the TV show Mahou Shoujo Madoka Magica. Dreaming Mary is an original adventure game in a sidescrolling format, made using the free RPG Maker VX Ace Lite.