The "Link Finds" fad is based off a scene from The Legend of Zelda: Ocarina of Time where Link opens a treasure chest to get the Kokiri Sword.

Origin

According to YTMND Wiki, the earliest evidence of this meme is the site created by the YTMND user Ravager, which features Link finding Milton Waddam's stapler. Since then, spinoffs in YTMND and YouTube have been showing Link finding many items, including a Nintendo 64, ninjas, bicycles, and even the Spanish Inquisition.

Compilation of YTMND fads:

Link finds an AK47 (somewhat NTSF):

Link finds a Lazor:

Link finds Dr. Octagonapus:

Link finds Weegee:

Link gets…: