50

50 was Wiki Cap Soldier's transformation during the final moments of The Stolen Pan (Finale), immediately after Soldier took the pan Wiki Cap Soldier had fought so hard to get back. 50's road sign has the same colour scheme as 20's road sign. In the only scene that 50 appeared in, 50 was much larger than Soldier, and was surrounded by four stand-posed Rather Festive Tree Engineers. shaking its head and arms towards Soldier whilst violently screaming. It began the destruction of the "The Stolen Pan" universe in order to punish Soldier for what he had done, but Soldier escapes through use of a Demoman. It is unknown what has become of 50, as it is either non-existent or still lives in an indeterminate location.

Trivia

 * The 50 road sign in Half-Life 2's source files actually has the colour scheme of 30, not 20. A manual texturing job was done to change the colour scheme.