on damage:
    name of attacker's tool is "&b魔法の剣"
    if attacker's max health is 20:
        set attacker's health to 40
        send "&b一時的に最大体力が20上昇した！" to attacker
        wait 10 seconds
        set attacker's health to 20
        send "&b最大体力の上昇が切れた！" to attacker