That would have been the Recipe for Disaster quest + sub-quests.
There probably won't be another special quest for quite some time. The first special quest, A Recipe for Disaster, was released in honor of their 100th quest.
It's currently not possible to undo a quest in RuneScape.
The legends quest on runescape is not gone, I suggest that you check again.
A quest on Runescape is an adventure that puts you in a conflict, you solve it and you get rewards like money, skill experience points, quest points, and items.
If you quit runescape...
There are many websites where one can get advice on completing a Runescape quest. The Runescape website itself offers advice as does the website Tip.It.
The quest Swept Away was released in RuneScape at the same time as the Halloween event in 2008.
The quest is called "The Chosen Commander".
You have to do the quest "Shield of Arav" for help on the quest go to Tip.it it's a website that i use most for runescape quest guides, skill calculators, ect.
The quest is Wolf Whistle and you can buy a dog at the store in Taverly after the quest.
By following all the requirements for the quest or you can go on a runescape help site. Here's one: www.runehq.com
You will need to complete the "priest in Peril" quest.