Give the Sister of Mercy's Heart to Sunny
After defeating the Sister, take her heart and continue into the Labyrinth. Pain Pillar 4 is on the main path immediately after entering this return section.
What I checked
This short heart-delivery objective is documented in PowerPyx's walkthrough, checked on 14 October 2026.
Heart delivery and health upgrade
Before leaving the arena, collect the Sister's Whip as well as the story heart. The whip can be sold later; it is not the item used to advance Sunny's task.
- Leave the completed arena and enter the Labyrinth route.
- Activate Pain Pillar 4 on the main path.
- Continue the heart-delivery progression to Sunny.
- When Hunt Marlowe returns, proceed toward the field with Leviathan's sweeping beam.
Check the next pillar separately
PowerPyx reports that the all-Pain-Pillars trophy can unlock early here. That does not establish that every remaining upgrade has been collected; keep checking the final Pain Pillar in the factory route.
Suffering Pillar 5 belongs to the following beam field, covered under Hunt Marlowe.
Questions
Where is Pain Pillar 4?
On the main Labyrinth path immediately after the Sister of Mercy fight.
Keep reading
Sources
- PowerPyx walkthrough — Give The Sister of Mercy's Heart to Sunny and Pain Pillar 4.