From Team Fortress Wiki

“ — Dadliest Catch publicity blurb "Don this Octodad disguise and demonstrate to the devilish enemy that you are dad enough to win!" ”

The Dadliest Catch is a community-created promotional cosmetic item for all classes. It resembles the head of Octodad from the game Octodad: Dadliest Catch. The back of the head flops around as the player moves.

This item can only be worn around Halloween or during a Full Moon; at other times of the year, it does not appear in gameplay, unless the server has Halloween mode enabled. However, it can be equipped at any time and can still be viewed on the loadout screen even when it is not visible during games.

This item is awarded in Genuine quality to players who purchase Octodad: Dadliest Catch on Steam.

The Dadliest Catch was contributed to the Steam Workshop.

October 29, 2014 Patch (Scream Fortress 2014)

[Undocumented] Added Dadliest Catch.

October 30, 2014 Patch

[Undocumented] Renamed Deadliest Catch to Dadliest Catch.