The entire film is about a demon evocated when playing a game. The demon itself can be scary in both voice and appearance, we can see several closeups of his face which can be frightening to young audiences.
When a candle goes out, it must be re-lit in ten seconds. This contributes to keep the tension high, since sometimes it tooks quite a lot of attempts (and sometimes they fail to do so)
quite a lot of jumpscares throughout the film, especially related with the grandmother appearing suddenly.
the grandmother sometimes appears to be possessed, as we hear her saying repeatedly "red is the color of your blood!"
The entire movie took place between midnight and 3:33AM, with no lights on apart from three candles held by the participants. As a result, all the frightening scenes are even more intense because of the dark.
A girl approaches a humanoid figure under a bed sheet. Later we learn that was only a manikin, albeit quite frightening.
After the candle burn out, the manikin is seen moving when the man doesn't look at it. It then disappears, and, moments later, the midnight man appears.
The ending was so bad that I'm now ascared of everything.