Crystal trinket

The crystal trinket is a reward from Arianwyn for completing Mourning's Ends Part II. It can be used to enter the Temple of Light after the quest. This requires mourner gear also, since the entrance is via the Mourner headquarters' basement in West Ardougne. However, if you've completed Within The Light, you can use the "Temple" option on a charged crystal teleport seed which will drop you off right outside of the Temple of Light, past the trapdoor and the dark beasts, bypassing the need for the mourner gear.

If you lose it, you can obtain another one from Arianwyn on the ground floor of the altar in Lletya.

If you try to enter the temple after completing the quest without the trinket in your inventory, you will be bounced back and get the message "A strange force blocks your path." When crafting death runes through the Abyss, however, this is not necessary. The same is true if you use a wicked hood to access the death altar.