The phrase "clearing levels" means moving forward and completing different stages or challenges in a game, often to progress to the next level or accomplishment.
Sentences with «clearing levels»
While clearing the levels of all objects isn't the most fun activity in the game, the money is well worth it in the late game. (switchera.net)
First things first, I'm sick of people saying that you can clear a level in x amount of time «if you want to». (metacritic.com)
One SP is obtained by clearing each level, but further SP can only be gotten by meeting score goals within a level. (playstationlifestyle.net)