It has Aura Sphere, Ancient Power, and Metronome. (Metronome's just for fun) It's ability is Serene Grace.
Neither. Air Slash is a good move in order to fully abuse Serene Grace.
Last Resort and Sky Attack are both Physical moves, and Togekiss has a really measly attack. Sky Attack also needs 2 moves to take effect, and Air Slash will deal more damage over 2 moves anyway.
like fondant said Sky attack isnt very useful. Togekiss is used to be annoying. Go with ParaFlinch. Lefties or Kings Rock
Aura Sphere: for a great Damage move
Metronome: If you are a big fan of it put it. but I wouldnt recommend it
Heal Bell: Great Support move