You have to keep following the road to the right of the psyduck until u get to the next lake. Cythia will then give it to you :)
In Pokemon Diamond the TM 90 is the move substitute.
yes as long as the move is available anywhere in the gamealthough Pokemon is awesome
It stands for technical move. there are lots of them on diamond.
mew
you mest get the hm strength.
hearthome city
Pastoria City
eterna city
you can buy it in veilstone
in the great marsh
you teach a Pokemon that move or use a TM
No, not all Pokemon in Diamond can learn Hyper Beam.