Also called the Overcharged Vial Quest

In a house to the West of the Goblin Camp (east of the RST) (2370,742,0), you will find a red-robed mage named Nelaryd.

Talk to him (guess, chance, look, yes, continue, then turn). He will first perform two impressive (or not) demonstrations of his magic!
Next, you will need to talk to him again (service, new potion, help, forgotten cave, yes, dozen, teleport), and he will ask you to bring him some leaves he needs to prepare a new potion.
Agree to be teleported by finishing the conversation with teleport. You will find yourself in an empty room, except for a vortex you must enter.
Make sure to protect yourself before jumping into the vortex and prepare for battle against the trees.

You arrive in a place full of demonic trees. At the entrance, there is a Dimensional Nexus where you can take refuge if necessary (if you have access).

Break Demonic Trees to collect 10 Tree Leaves directly in your inventory (a message appears every time you collect a leaf).
The drop rate is not great, and sometimes you need to kill many demonic trees to get all the leaves. These demonic trees only attack upon contact.
Note: This quest can be completed in a group, with the leaves appearing in each member’s inventory simultaneously.

Once you have collected 10 tree leaves, use the vortex at the Northwest of the map (804,1495,1) to return to Nelaryd.
Talk to him, and he will take 10 of your leaves. If you collected more, know that they are useless, they cannot be dropped, and each weighs 1 unit of encumbrance (destroy them).
Continue the conversation to choose your reward (craft, then mana potion or life potion).

Gain (choice of):

• An overcharged life vial (life regeneration, +8 HP every 5 seconds, for 20 minutes, 60 charges)
  * An overcharged mana vial (mana regeneration for 20 minutes, 60 charges)
  

Learn more about the potions by saying: usage or learn.

You can then recreate overcharged life or mana vials (18 charges of 20 minutes).
Simply double-click in your inventory on a Opuntia vitae leaf for life charges or an Opuntia magicae leaf for mana charges.

These can be found in the Prickly Pears located on each island:

• Arakas :
  • South of the RST (2353,877,0)
    

    * At the southernmost point of the continent (2155,1655,0)  

• Raven's Dust :
  • Between the two mountain ranges southeast of Grott (1150,2605,0)
    
• Stoneheim :
  • Northwest of the pink skraug camp, near the mountain range of Mordenthal castle (397,131,0)
    

Note: The recharge time for the Prickly Pears is 5 hours (300 minutes).