Many observers may notice the absence of the lambda (λ) from the Half-Life logo; something consistent across the series' branding (with the exception of the title screen of Half-Life 1's original release). While it isn't explicit, the lambda is present in the form of the Y in ALYX, as a vertically-flipped lambda. Its presence is hinted at by the Y fading out noticeably slower than the rest of the logo in the game's branding.