First encountered during the Big Chompy Bird Hunting quest, he shows players how to hunt chompy birds. After the quest, players who kill a large number of chompies (minimum of 30, maximum of 4,000) will be able to claim some of Rantz' feather hats.
Rantz is also encountered during Recipe for Disaster, when players must run an errand for him in order to learn how to catch jubblies. Players will also have to do a "small favour" for Rantz during the One Small Favour quest.
Rantz will give players the ogre bow during the Big Chompy Bird Hunting quest and afterwards if you should it lose it, he will sell you another.
If you lose your ogre bellows, walk north from Rantz until you get to a cave (note: the cave is NOT on the world map) and go in. In the north-west area of the cave there should be something with a huge rock on top of it. Press unlock locked chest then search it for new ogre bellows.
Players who have completed the Western Provinces Diary can talk to Rantz and he will give players up to 25, 50, 100, or 150 free ogre arrows per day, depending if the easy, medium, hard, and elite diaries are completed, respectively.
- His name is an obvious pun on the term "Rants" which is a way to describe criticism. This would pertain to the fact that Rantz is always criticizing the player during Big Chompy Bird Hunting.