Portal Gun Device — White, Neutral

1024 × 768

Dead Dreamer: Decay of Destiny

1024 × 768

Cave Johnson Character — White

1600 × 1200

Four Colored Portals

1440 × 900

Scientist with Patient

1600 × 763

Two Figures on a Cliff — Brown, Dramatic, Sunset, Digital Art, Castle

1920 × 1080

Mass Effect Logo — Black, Dramatic

1920 × 1200

Portal turrets with red laser

1920 × 1200

Hands Holding a Cube — Black, Neutral

2400 × 1920

Portal 2 Logo — Blue, Minimalist, Digital Art, Text

1440 × 900

Stick Figures with Quotes

1280 × 1024

Portal turrets in a dark room

1600 × 900