What are they used for ??

buying weapons.what i want to know thought is how you obtain them

You get them by killing the monsters in thzaar.

Tokkul is a relatively new currency, used primarily in the Tzhaar city, located under the volcano in Karamja. In fact, the Tzhaar city runs exclusively on Tokkul, and will not accept coins. The Tokkul are round and similar to coins, except Tokkul is made out of a hard obsidian stone, rather than gold. Tokkul can not be traded with other players.

 

 

 

 

 

 

 

Tokkul can be acquired several ways, but only in Tzhaar. You can kill most of the npc's that wander the city for Tokkul, or sell items to the shops. You also have the option of a couple mini-games located in Tzhaar.

 

 

 

 

 

 

 

The Fight Pits is a good place to earn Tokkul, by being the last one standing in an all out, every man, woman and child for themselves, royal rumble. However, if you're not a very high level, and if the pit has several players, being the last to survive can be difficult.

 

 

 

 

 

 

 

A more sure fire way to get Tokkul is the Fight Caves. Unlike the Fight Pits, you are not competing against other players, but rather monsters. Also, you do not have to reach the end to collect Tokkul. If you die, you re-appear outside, with full health, prayer, and a number of Tokkul that reflects how long you lasted in the caves.