Explosive perfect shield was a special effect in Super Smash Bros. 4. It was considered the best bonus available and was a centralizing force in the early amiibo metagame. Hence its name, Explosive perfect shield generated a damaging explosion whenever its user perfect shielded an attack.
Explosive perfect shield was popularized by Glenn. amiibo in Smash 4 were highly defensive; early tournaments essentially revolved around which fighter could best utilize Explosive perfect shield. The bonus carried several amiibo to victory, including surprising characters who, without the help of Explosive perfect shield, would have never made it to grand finals.
It was eventually banned; the community agreed that it was boring to watch and made tournaments dull. In competitive Super Smash Bros. tourneys, elements of the game are not banned due to being boring; in the amiibo metagame, this is different, as it is much less popular than competitive Smash and needs to retain all the viewers it can get. Explosive perfect shield was banned alongside Critical-hit capability. It did not return as a Spirit effect in Super Smash Bros. Ultimate.