I had trouble with this and had to ask for help on IRC so I'm posting it here for anyone that needs help.
To get an ExtremeSpeed Dratini, you have to defeat Clair and go to the Dragon's Den. I'm not sure if you need the Dragon Fang but I got it anyway. Enter the Elder's House and answer his questions -- they're the same questions as the ones from Crystal (Serebii has details on which answers to choose). I believe, when you click bad answers, the Elder turns and mutters something to himself -- that's a sign you did something wrong.
After answering all the questions Clair runs in and they have a chat; she gives you the Rising Badge and leaves. Go to leave the Dragon Den and you'll find Clair near the exit. Talk to her for a bit and she'll give you her TM. Go back to see the Elder and he'll give you the Dratini. I've heard reports of ExtremeSpeed being the last move Dratini has, replacing Dragon Rage. My Dratini had ExtremeSpeed replacing the first move, replacing Leer I believe.
On a side note my Dratini is Mild with pretty good IVs 8-)
To get an ExtremeSpeed Dratini, you have to defeat Clair and go to the Dragon's Den. I'm not sure if you need the Dragon Fang but I got it anyway. Enter the Elder's House and answer his questions -- they're the same questions as the ones from Crystal (Serebii has details on which answers to choose). I believe, when you click bad answers, the Elder turns and mutters something to himself -- that's a sign you did something wrong.
After answering all the questions Clair runs in and they have a chat; she gives you the Rising Badge and leaves. Go to leave the Dragon Den and you'll find Clair near the exit. Talk to her for a bit and she'll give you her TM. Go back to see the Elder and he'll give you the Dratini. I've heard reports of ExtremeSpeed being the last move Dratini has, replacing Dragon Rage. My Dratini had ExtremeSpeed replacing the first move, replacing Leer I believe.
On a side note my Dratini is Mild with pretty good IVs 8-)