The death-rune is a semi-rare rune used in blast spells. These have a street price of around 1000 coins each. A good way to farm large amounts of death-runes is to keep kittens in your inventory until they are fully grown, then sell the cats to civilians in West Ardougne for 25 death-runes each. Underground Pass quest rewards players with 15 Death-Runes and 30 Fire-Runes.