From the RuneScape Wiki, the wiki for all things RuneScape
The
Death talisman is an
item that allows players to enter the
death altar located in the temple used during the
Mourning's End Part II quest. It can be obtained by killing
Dark Beasts with level 90
Slayer or catching
dragon implings. They are also obtained during the
Mourning's End Part II quest. After obtaining a talisman from the quest, a player can receive another one by doing yet another wish-list given by the dwarf. Additionally, they can be purchased from players. It can be combined with a
tiara to make a
death tiara for 50
experience at the death altar by using the tiara on the altar. This will make the talisman disappear, but the tiara can be used in just the same way and can be worn. Both the tiara and the talisman allow players to use the
Runecrafting skill. Players will have to show this talisman to
Wizard Elriss (amongst other talismans) to obtain the
Omni-talisman.