This is the creature schtick of the same name, Feng Shui, p 126.

You are immune to a particular form of damage and suffer no Wound Points from such attacks no matter what. For each schtick you spend you become immune to an additional form of damage. Your choices and exceptions must be relevant to what you are and the campaign. 

You are not only immune to damage; you actually cannot be directly affected by that force in any way. But you can still be indirectly affected by a creature that modifies it's own abilities through a power you are immune to. Thus, a sorcerer could turn invisible, and you would not see him. A Creature may have Abysmal Spines modify it's damage rating, but the damage itself is till from an Unarmed Attack.

Damage Immunity is much more appropriate to NPC monsters than to player characters; many plots revolve around finding the sole way f slaying some creature immune to normal weaponry. A Damage immune PC can expect to become quite famous, and thus have his weaknesses known and exploited.

Here is a listing of common damage immunities. Note that many of these overlap. The GM may freely design other varieties. Some types of Damage Immunity may not be absolute, only reduce any Wound Points you take to one point.

Air

You are immune to all air-based effects, such as the Movement schtick of sorcery, lightning bolts and telekinetic attacks, falling damage and poison gas.

Blast

Immune to almost all effects of the Blast Sorcery schtick, Arcanowave blasters and the Blast Creature Power. You are not immune to those blasts you yourself know; this costs one extra schtick. You can opt to be immune to only your own blasts for only one schtick pick. Note that some Blast effects have special rules applicable to Damage Immunity, and these supersede this power.

Creature Powers

Immune to most Creature Powers. You are not immune to those Creature Powers you yourself know; this costs one extra schtick. You can be immune to only your own Creature Powers for one schtick pick. Note that some Creature Powers have special rules applicable to Damage Immunity, and these supersede this power.

Earth

Immune to damage from falling, being crushed, vehicle crashes etc. You cannot be grappled, held or entangled. You can walk on any surface, no matter if it could ordinarily carry your weight. This is also known as damage immunity to Accidents. 

Fire

Immune to explosions, fire, energy weapons etc. 

Fu

You are immune to all Fu powers, including Transformed Animal and Race schticks. Characters using Fu powers to attack you simply fail.

Guns

Immune to all bullets, arrows and other missiles fired using Guns except one specific type or material.

Impaling

You are immune to piercing weapons, such as bullets, arrows, sword thrusts, knives and spears. Delivering a slash with a piercing melee weapon is a stunt. Impailing attacks can cause you a maximum of one wound point per projectile; automatic fire, shotguns and such can still work pretty well.

Damage Immunitty to impale often indicates that you are an amorph being with no sensitive interior organs. Very common for cthulhuoid creatures.

Influence

Immune to social and mental control and influence, such as Seduction, the Influence schtick of Sorcery, the creature powers Hypnosis, Possession and Domination, as well as the Imperial Whisper Fu schtick and similar powers. You are not immune to Deceit.

Life

You are immune to dangers harmful to living, organic creatures. This is typical of golems, undead and similar non-living creatures. You cannot drown, starve or suffocate. You are not discomforted by normal extremes of temperature, but suffer normal damage from heat and cold attacks. You are also immune to poison and disease, but not to acid. You never sleep. Your body is immune to Healing sorcery and to Polymorphism, but can be affected by Conjuration or Death magic, as appropriate.

Melee Weapons

Immune to hand-to-hand weapons except one specific type or material. This includes throwing and brawling weapons, but not grenades (you need Fire for that).

Sorcery

Immune to all Sorcery schticks and the effects of magic items that imitate sorcery, except Blast and Summoning. 

Summoning

Immune to the Sorcery schtick Summoning. You also become immune to other effects specifically targeting supernatural creatures, such as the arcanowave device Wave Suppresser. This effectively removes the supernatural stigma from you. You do not suffer or benefit from the Supernatural Creature junction modifiers. Few creatures should be allowed to take this schtick, those that are are typically mundane creatures for their world but with powers that are best expressed as Creature Schticks (Large birds, Pegasi, Giant Spiders).

Unarmed Attacks

Immune to unarmed attacks, including Fu and Animal schticks used without weapons. This does include close-combat Creature Powers or Arcanowave Devices such as Abysmal Spines or War Claws. Brawling weapons such as knuckles and cyberclaws are considered melee weapons.You must select some form of unarmed attacks against which this power fails, such as unarmed Fu or Creature powers, animal attacks and so forth.

Water

Immune to all kinds of poisons, cold, stickiness, liquid attacks and similar effects, such as Foul Spew, acid and even drowning. You won't ever slip. You cannot move freely underwater, that requires the Amphibian schtick.