the valknut- vikings painted this on their shields to call the Valkyrie to take them to Valhalla if they were killed, Jake had this tattooed on his forearm in honor if his viking decent/roots. Along with some ancient runes.
50 Valknut Tattoo Designs For Men - Norse Mythology Ink Ideas
The Viking Runes. The eldest runestones, inscribed with Norse runes, date from the century. These were the Elder Futhark runes. However, the most of the runestones were created during the late Viking Age and thus inscribed with theYounger Futhark runes.