Mortal blow

Mortal blows, also known as instant death attacks, are a class of special attacks from Super Mario RPG: Legend of the Seven Stars. The term refers to any special attack that can one-hit down a party member, regardless of either the party member's or the enemy's stats (such as Hit Points, attack, and defense). Attacks of this variety include Magnum and Shaker. Mortal blows can be blunted by pressing at the right time during attack, allowing the party member to keep either one HP or all HP. If the timing was perfect, the party member keeps all HP as though nothing happened, but if it is slightly off, the party member still survives with a single Hit Point. Certain accessories, such as the Jinx Belt, Safety Ring, and Quartz Charm, can prevent mortal blows from having any effect.

Mortal blows
Attacks marked with an asterisk (*) can be blunted by pressing.
 * Blazer - Blaster, Big Bertha
 * Fear Roulette - Ding-A-Ling
 * Magnum - Smithy (Tank Head)
 * Migraine* - Pulsar, Body
 * Psyche!* - Cluster
 * Scythe* - Glum Reaper
 * Shaker* - Boomer
 * Silver Bullet* - Jinx, Jinx Clone