It's more or less instantly, once you 'complete' the quest to put the egg in the cave, you should be able to get straight into the Hatching.
the eggs have already hatched so just complete the tasks get the egg watch the short and talk to Twilly (the red moglin)
The only way is to do the quest... It doesn't take that long tbh...
type /join death then take the quest
Dragon Slayer is a moderatley long quest, compared to some of the Member quests such as Monkey Madness, Legends Quest, and While Guthix Sleeps. If you follow a guide it shouldn't take you more than a few hours. You can find a guide for all RuneScape quests at www.RuneHq.com
no all it does it does is pop its head out of its shell and then deos a weak ice attack
Without knowing which game you are playing it is impossible to say how long it will take. Depending on the game, a quest can take no time (the game will give you credit for a quest that you completed before accepting it), or a quest can take the entire time you spend playing (those quests that you sometimes get at the very beginning of the game that ask you to save the land or kill the big boss, which you can't do till weeks, months, or years later (depending on how long and often you play it).
I have placed a link below that should take you to a quest guide for this quest.
From the bounty hunting quest from robina
well, legend of the dragon was made quite a while ago. it took them about a year to complete it.
you enter your bathroom and take a shower. that's how you take a bath. -Bob Howe
8 hours long does the gummy dragon takes to hatch on dragon city.