To unlock Gelena at the Tree of Whispers in Diablo 4, you need to follow specific steps tied to the Season of Witchcraft content. Gelena is a key NPC who helps you craft Coven’s Debt Scrolls, which are essential for gaining large amounts of Coven's Favor. Here's how to Diablo 4 Items unlock her:

Steps to Unlock Gelena at the Tree of Whispers:
1. Progress Through the Season of Witchcraft Campaign
Start by working through the Season of Witchcraft story. You need to complete the main seasonal campaign to unlock important seasonal mechanics, including access to Gelena.

2. Earn Coven’s Favor
You’ll earn Coven’s Favor by completing Whispers of the Dead challenges. These challenges require you to buy Diablo IV Items complete specific tasks in various regions, such as killing certain enemies, collecting items, or protecting NPCs.

Completing these tasks rewards you with Grim Favors. For every Grim Favor you turn in at the Tree of Whispers, you will earn Coven’s Favor. This is crucial for progressing through the Season of Witchcraft and unlocking new content.

Coven's Favor will unlock various rewards, including side quests, gear caches, and more powerful witchcraft powers.