Instructions
Capture Khezu
Complete the Village Elder Quests until the hunter is given access to the quest "Shadow in the Snow." Accept the quest.
Prepare for the quest by upgrading the hunter's weapons and armor. His weapon should be at least third-tier, such as the Viper's Bite or the Katana Gospel. His armor should provide at least 40 defense. It is helpful if he has developed the armor skill Earplug or has a shield equipped, because this will prevent him from being affected by Khezu's scream ability.
Go to area three if this is the hunter's first time fighting Khezu. Otherwise, look for it in areas six, seven, eight, or one, in that order.
Paintball Khezu immediately upon finding it. Khezu can choose to fly away from the battle at any time. Having the wyvern paintballed makes it easier to locate and gives it less time to heal while the hunter is tracking it.
Weaken Khezu. The exact method for attacking Khezu differs greatly depending on what weapon the hunter is using. Gun weapons are the easiest to use in the battle, because Khezu will coat its body in an electric shield that damages the hunter if he gets too close. Fire the gun at its head and neck for maximum damage. Also try setting large barrel traps when Khezu flies to new areas. When it lands, shoot the traps to deal a lot of damage.
Watch Khezu closely. When the wyvern stands still for a few seconds without doing anything, it is about to fly to area three to sleep. Let Khezu escape and follow it to area three.
Place a trap directly in front of Khezu and attack it to wake it up. Khezu will rush straight into the hunter's trap. Throw two or three tranquilizer bombs at Khezu until it is successfully captured. Capturing Khezu is better than killing it because the chances of getting Electro Sacs are much higher in a capture.
Repeat the quest until you have the desired number of Electro Sacs. To repeat the quest, select it from the three star quests menu when talking to the Village Elder.
Using Trenya's Boat
Complete the quest "A State of Crisis."
Travel to the Pokke Farm. The farm is southeast of the hunter's house in the village.
Unlock Trenya's boat. You can do this by spending five hundred Pokke Points or by purchasing the Trenya boat download from the PlayStation Store.
Send Trenya to the Snow Mountains for 500 points.
Complete a slaying, hunting, training school, or treasure-hunting quest.
Return to Trenya and see what the expedition has yielded. There is a small chance that you will receive one or more Electro Sacs.
Repeat steps four through six until you have the desired number of Electro Sacs or run out of Pokke Points.
Trading a Shakalaka
Gain a Shakalaka Inheritance. These very rare items can sometimes be carved from the shells a Shakalaka monster leaves behind when a hunter has defeated it.
Save the game. There is a small chance this method will not work and it takes less time to reload an old game than to hunt down another Shakalaka Inheritance.
Visit the Village Elder in the jungle area and choose to trade the Shakalaka Inheritance. There is an 80-percent chance that the Elder will give you an Electro Sac. There is a 20-percent chance that he will give you a Paralysis Sac instead. If this happens, reset and load your saved game.
Repeat the process until you have the desired number of Electro Sacs.