Pokemon that has Insomnia, Vital Spirit, the ones that are already asleep, Chesto Berry Pokemon and Lum Berry Pokemon. Now, the 3 last conditions don't act long ; berries can both be used only once, and being asleep means that you will wake up after a certain time.
Also, Magic Bounce Pokemon and Pokemon that use Magic Coat right before Dark Void may trap Darkrai into it's own trap.