Magic Guard prevents the Pokémon from receiving indirect damage, but does not prevent it from becoming afflicted by statuses that would deal such damage. Additional effects, such as being trapped by binding moves or having its Attack reduced by burn, are not prevented even though their damage is.
Magic Guard prevents damage caused by effects including weather, poison and burn, effects like
Curse and
Leech Seed, entry hazards, recoil (except from Struggle), crash damage, and damage from using
Mind Blown. Magic Guard prevents the damage inflicted by a Life Orb, but the holder still gains the power boost. Damage from confusion still occurs.
Magic Guard does not prevent direct modification of a Pokémon's HP through means other than damage, such as by
Pain Split,
Belly Drum,
Substitute, or a Ghost type cutting its own HP to use
Curse. Moves that cause the user to faint,
Destiny Bond, and
Perish Song can still cause a Pokémon with Magic Guard to faint.
Magic Guard didnt grants immunity to being fully paralyzed and no prevents of be poisoning from Toxic Spikes (but it still prevents poison damage).