Rhok'delar, Longbow of the Ancient Keepers
Rhok'delar and Lok'delar, Stave of the Ancient Keepers were Hunter only bow and staff rewarded for completing a challenging quest started by the Ancient Petrified Leaf, which was a drop out of Majordomo Executus' chest in the Molten Core. The weapons were very prolific in the early MC/BWL days but most raiding Hunters would replace Rhok with one of the weapons in BWL, the Gun from Ebonroc or the Crossbow from Chromaggus. The bow really stood out for it's cool "living" style model and the staff was commonly seen on Hunters for the entire duration of Vanilla raiding as it was a good stat stick that Hunters didn't have to fight melee dps over.
Source
To acquire Rhok'delar and the accompanying Lok'delar the Hunter would first need to obtain the Ancient petrified Leaf out of Domo's chest in MC. This quest starter had a 50% chance to drop, the other 50% of the time was the Eye of Divinity for the Priest quest line.
Once the Hunter had their Leaf, they had to go to Felwood and talk to the petrified trees. The trees would give the Hunter a quiver in exchange for a Mature Blue Dragon Sinew which was a 100% drop off of Azuregos or could be farmed as a rare drop from the blue dragonkin in Azshara. Also the trees would tell the Hunter to go kill 4 demons around the world. Sounds simple enough, but this was no easy task. These demons had a fairly long respawn time and would despawn if more than one target was attacking them. This included other Hunters/players and even the Hunter's own pet. So the Hunter had to kite and kite well. If the demons made it to the Hunter it was almost a certain one-shot kill.
Many Hunters, who were regularly some of the shittiest players in the game, just couldn't do it. Some had other players do the demons for them. Ahazi asked Drewbie to do the quest for him because he was so shit. Drewbie didn't even main a Hunter but made short work of the quest demons because he wasn't total shit. Other players just gave up entirely and waited to be carried through new content that would just drop a weapon they could equip without going through quests to get.
After the 4 demons were defeated, the Hunter needed to kill Onyxia for the Enchanted Black Dragon Sinew. The Hunter could then combine the Sinew with the quest staff they had received for killing the demons to create Rhok'delar, Longbow of the Ancient Keepers.
Lok'delar, Stave of the Ancient Keepers
Originally, the Hunter could only use either the Rhok'delar or the Lok'delar because they were transform items, similar to the Benediction/Anathema. Many would use Rhok as their primary weapon until they got a weapon from BWL and then switch the quest bow to Lok'delar as it was a quality Hunter stat stick. However, on October 10, 2005, the 1.8 patch made it so that the Hunter could have both the bow and the staff and took away the ability to transform them, much to the joy of Hunters everywhere.
Legacy
With the 4.0 Cata pre-patch the old world of Azeroth (Kalimdor and EK) were remade. A side effect of this was that the areas in which the quest for slaying the demons were changed/removed. This meant that the quest could no longer be completed. Because of this the Ancient Petrified Leaf was removed from Domo's cache in MC. Any Hunter who had not already obtained their Rhok'delar by the end of Wrath was now SOL. The Rhok'delar and Lok'delar became very popular transmog targets for Hunters after the system was introduced in late Cata. One of the Challenge Mode rewards in WoD was a higher res "living bow", presumably paying homage to the Rhok'delar.
