In Valor Mortis, the Empty Ferrofluid Flasks and their associated Power Upgrades are crucial for survival, significantly boosting your healing potential. These items not only provide an additional Ferrofluid Flask but also enhance the potency of each flask, ensuring you can tackle perilous areas and challenging bosses with greater confidence.
Empty Ferrofluid Flask Locations
Finding these extra flasks is highly recommended. The first Empty Ferrofluid Flask is located in a chest next to The Climb Lantern, shortly after you acquire your initial ranged weapon and learn about Weak Spots. After obtaining the Grapple ability, head to the burning village across the pond from the Marketplace Lantern in the Fallen Village area. Following the grapple points will lead you to a small wheat field; the flask is in a chest at the back of this area, guarded by an enemy.
Within the Caverns, from the Old Mine Lantern, proceed into the mines. Utilize the Stasis ability to freeze a crate, allowing you to cross the room. Continue further into the cave, and on the first left, freeze the cog of a moving platform to reach a chest containing an Empty Ferrofluid Flask. Be sure to clear the enemy positioned above the cog beforehand.
Ferrofluid Flask Power Upgrade Locations
To enhance the effectiveness of your existing flasks, seek out the Ferrofluid Flask Power Upgrades. One such upgrade can be found from the Valley of Ashes Guidepost Lantern by following the path left to a cliff edge with a boardwalk. Traverse over crates to find an enemy guarding a chest with the upgrade. Following your first encounter with Howler enemies, clear the encampment near the Military Camp Lantern. A small camp with a blue memory and a cannon can be found; interact with the cannon to open a gate near the area's Lantern. Progress through this new path, defeat the subsequent enemies, and a chest containing the upgrade awaits.
In the Fallen Village, an upgrade is located in a chest just before a Nephtoglobin node that opens a shortcut back to the Fields Lantern. From the Marketplace Lantern, enter the open barn and proceed upwards. Jump onto the rafters of the next building, and the upgrade will be in a chest within the structure below. After navigating the bridge with the large enemy in the Vale of Wrath and unlocking the shortcut, proceed past the locked gate. Climb rocks, wall-ride to the interior of a building, and use a lever to open the gate (freezing its cog with Stasis). The upgrade is in a chest immediately to your left once through the gate.
From the Ship Graveyard Lantern in the Vale of Wrath, reach the ship graveyard itself. Board the large central ship and look in the lower cargo storage for a chest guarded by enemies. This chest holds a Ferrofluid Flask Power Upgrade.
Additional Upgrades and Vendor Offerings
Completing the 'The Curious Case of Seamus Diggory' side quest in the Cursed Hollow, accessible from the Silent Cannons Lantern, rewards players with a Power Upgrade regardless of the final choice. After defeating the High Justicar Aurelius, Last of the Faithful boss in the Outskirts, a chest containing a Ferrofluid Flask Power Upgrade will be immediately accessible.
In the City of Orphans, utilizing shortcuts from the Tribunal Square Lantern leads to an area with a large statue and wooden fort. A grenadier guards a chest containing an upgrade. Within the Sewers from the Sewers Lantern, use the grapple hook twice to reach a room with a chest holding another upgrade. In the University, after progressing through the Main Hall Lantern and a shortcut, use the Shield Transmutation to traverse a poisonous hallway. An elevator ride down leads to a chest behind a statue.
Accessing the Lift Shaft in the University requires finding the Lift Shaft Key. After riding the lift down, proceed through a dark passage. Following this passage leads to a trapped chest containing a Ferrofluid Flask Power Upgrade. In the Fortress area, from the Traverse Lantern, proceed past enemies and utilize Nephtoglobin formations to reach ruins on the opposite side. A chest within these ruins contains an upgrade.
Additionally, Louis in the Abandoned Church offers an Empty Ferrofluid Flask for 5000 Catalysts. He also sells three Ferrofluid Flask Upgrades for 3000 Catalysts each, with more potentially becoming available as the story progresses. It is advisable to check his inventory regularly throughout your journey.