What it does
Spiky Shield blocks all damaging moves for the turn, same as Protect. The addition: if the attacker uses a contact move against the shield, they lose 1/8 of their max HP. Non-contact moves — Special attacks, most spread moves — are just blocked with no penalty.
In doubles, the Protect mechanic itself is one of the most valuable in the format: your Pokémon survives the turn while your partner moves freely. Spiky Shield puts a cost on the opponent's decision to attack into it with physical contact moves. Individually 1/8 is manageable, but stacked against burn, poison, rocky helmet, or weather chip, it accelerates the HP erosion significantly.
Spiky Shield and Protect share the same consecutive-use success-rate halving mechanic — use Protect-family moves back to back on the same Pokémon and the success rate drops by half each time. You cannot spam it. Alternating with attacking or support moves is the standard approach.
Feint bypasses Spiky Shield, same as Protect. This is a common high-level counter-play.
Who runs it
Glimmora (72% usage) is Poison/Rock, Special Attack-oriented, and uses Spiky Shield as its standard protection move. The extra contact chip penalizes opponents who try to smash through with physical moves — physically attacking Glimmora rather than hitting it specially gives them a 1/8 tax each attempt. Its Poison typing pairs naturally with passive damage accumulation.
Chesnaught (71% usage) is Grass/Fighting with high Defense. Physical attackers already struggle to break through its raw bulk; Spiky Shield adds an additional layer where even the attempts that get through Protect are punishing. Forcing contact-heavy opponents to chip themselves on Spiky Shield while failing to deal meaningful damage is Chesnaught's defensive identity.
How to use it
Use it in the same situations as Protect: your partner needs a safe turn to do something — set up Trick Room, establish Tailwind, complete Mega Evolution — and you need to survive the turn.
The choice between Spiky Shield and Protect comes down to the opponent's attack type. Against physical-contact-heavy opponents, Spiky Shield adds real value. Against Special attackers, either move does the same job and the contact chip never triggers. Either way, the consecutive-use frequency decay applies, so track how recently you used a Protect-family move.
Tips & strategy
Feint bypasses Spiky Shield just like Protect. When you read a Feint coming, an aggressive play often beats staying behind the shield.
The classic doubles rhythm is alternate: one Pokémon protects, partner attacks. Spiky Shield in this framework adds passive chip on top — opponents focusing the shielded side pay a contact tax, which is a meaningful deterrent against physical contact attackers.
For Glimmora: its Toxic Debris ability scatters Toxic Spikes when hit by physical moves. Spiky Shield prevents it from being hit at all, so Toxic Debris does not trigger on the protected turn. The two effects don't overlap — if you want Toxic Debris to fire, you need to actually take the hit.