League of Legends' graphical quality is based on four main settings (character quality, environment quality, effects quality, and shadows) as well as a few other settings that can be toggled on or off. The main thing to keep in mind is that higher settings will result in more impressive visuals, while lower settings will lead to improved performance if the game isn't performing as well as you'd like on the higher settings.
Each of the four main graphical settings can be set to one of five levels: Very Low, Low, Medium, High, and Very High. For those who prefer not to fuss with each individual setting, there's also a large slider that will adjust the overall graphical settings between seven levels: Very Low, Low, Medium Low, Medium, Medium High, High, and Very High.
Below is what the game looks like based on those seven overall graphical settings. Each of the following screenshots was taken at 1920x1080 resolution. Click on any of the images in this guide to see them in greater detail. If the 7 images below look too similar to make out any changes, check the zoomed-in image that compares Very Low, Medium, and Very High.
Very High
The game really feels alive at Very High. Textures are neat, lines are clear, effects dazzle, and character models properly show off the game's great art style.
High
It's difficult to detect much visual degradation between Very High and High. You may notice a performance improvement of ~2% on High compared to Very High.
Medium High
The Medium High graphical setting keeps all settings on High except shadows, which are turned to Medium. In our testing, we could not tell a significant difference between the High and Medium High visual settings in regards to either performance or visuals.
Medium
Changing to Medium settings is where you really start to see significant improvements in performance at the cost of visuals. Textures and shadows are less sharp, but performance is 15-20% better than having everything at Very High/High.
Medium Low
Medium Low might give you minor performance improvements over Medium. Expect performance ~20% better than Very High/High.
Low
Low settings set shadows to off. While the visuals are significantly worse, expect 25-30% better performance than Very High/High.
Very Low
At Very Low settings, textures are muddy, lines are jaggy, and shadows are still gone. For all its ugliness, Very Low will perform ~40% better than Very High/High.
Let's zoom in and take a closer look at Very Low, Medium, and Very High:
The differences between Very Low and Medium are immediately apparent: The textures and character model are much cleaner.The difference between Medium and Very High are more subtle, but most apparent are the improved details in the shadows and subtle character textures. Once again, click on any of the images in this guide to view them in greater detail.