How to increase inventory space in Final Fantasy 16

As you’re playing Final Fantasy 16, you’ll be bombarded with the message: “Insufficient inventory space. Potion used.” With a maximum of four potions and three high potions available to use in the beginning of the game, you’ll start to wonder when you can finally hold onto more potions. Luckily, you can increase your potion capacity by completing the side quests “Weird Science” and “Even Weirder Science,” but it will take some time to reach these quests.

How to increase your inventory size in Final Fantasy 16

In Final Fantasy 16, you can increase the amount of potions you can carry by completing the side quests “Weird Science” and “Even Weirder Science.”

‘Weird Science’ side quest location and walkthrough

Graphic: Johnny Yu/Polygon | Source images: Square Enix Creative/Square Enix via Polygon

To unlock the “Weird Science” side quest, you must first get to the “Out of the Shadow” main scenario quest and unlock Mid’s Dungeon in the Hideaway.

1. Speak with Owain to receive the “Weird Science” side quest. He will request you to get bomb ash, which can only be gathered from the Bomb King hunt.

2. Interact with the hunt board to find that the Bomb King resides in the Crock in Sanbreque.

Graphic: Johnny Yu/Polygon | Source images: Square Enix Creative/Square Enix via Polygon

3. Travel to the “The Dragon’s Aery” obelisk in Sanbreque.

4. Head to the Crock, which can be found at the northern end of the Imperial Chase.

5. Defeat the Bomb King. Watch out for the Bomb King’s large AOE attacks, and make sure to take out the bomb minions when they’re summoned.

6. Collect the three bomb ash on the floor, and give them to Owain at the Hideaway.

Image: Square Enix Creative/Square Enix via Polygon

Once you’ve successfully completed the quest, Owain will give you a treated potion satchel, which increases your carrying capacity for consumables. You can now hold the following:

• Six Potions
• Four High Potions
• Three Strength Tonics
• Three Stonekin Tonics

‘Even Weirder Science’ side quest location and walkthrough

To unlock the Even Weirder Science side quest, you must finish the “Weird Science” side quest, and you must reach the “Across the Narrow” main scenario quest.

1. Interact with Owain, who is located in Mid’s Dungeon in the Hideaway.

Graphic: Johnny Yu/Polygon | Source images: Square Enix Creative/Square Enix via Polygon

2. Head to Lostplume in Rosaria by teleporting to a nearby obelisk, and make your way to the quest marker.

3. Defeat the enemies blocking the spherical echo, and don’t forget to grab it before leaving!

Graphic: Johnny Yu/Polygon | Source images: Square Enix Creative/Square Enix via Polygon

4. Teleport to the Northreach obelisk, and travel to Advent, the southwest region of Claireview.

5. Defeat the woken enemies and collect the spherical echo.

Graphic: Johnny Yu/Polygon | Source images; Square Enix Creative/Square Enix via Polygon

6. Teleport to the The Korzjit Echoes obelisk, and travel to the Silent Sough.

7. Defeat the woken enemies guarding the spherical echo and collect it.

8. Return to Owain in the Hideaway, and give him the three spherical echoes to complete the quest.

Now that the quest is complete, Owain will give you an expanded potion satchel, which will increase the number of consumables you can carry. You can now hold the following:

• Eight Potions
• Five High Potions
• Four Strength Tonics
• Four Stoneskin Tonics

Now that you’ve increased your inventory space, you should upgrade your consumable potency as well!

Update (June 28): We’ve updated this post with another way to increase your potion capacity.