Price floor.
A floor, in real life, is at the bottom, below you — this then makes sense in business to say that a ‘floor’ represents the minimum value of something — in this case the price of video games.
In real life, a ceiling is above you, indicating that it could be used as a representative of a maximum value of something, like the price of a video game.
So, if we were to say that $120 was the ‘price ceiling’ for video games, then we would basically be saying that $120 is the most a video game could cost. If we were to say that $100 was the ‘price floor’ for video games, we would be saying that $100 is the minimum value that the price of a video game could assume.