Karxrida
Death to the Undying Savage
According to Bulbapedia, No Guard actually lets you hit Pokemon that are using Fly, Dive, etc.It doesn't work that way. If you use Sky Drop on Darkrai then it will be invulnerable, almost like Darkrai has used Fly or Dive, so you can't hit it with Machamp while it's in that state. If you want to do that why not just use Fake Out on the Darkrai and have your partner kill it?
http://bulbapedia.bulbagarden.net/wiki/No_Guard_(Ability)