Problem with skills Rpg maker 2000

I was wondering how I can create a skill that deals one damage to all enemies during a battle.  Whenever I set the Basis effect # for 1 or 0 it still deals arround 13 damage instead of the desired 1 damage.  Also is there a way of keeping the skill from getting better as the character goes up in levels?  When I tested this skill on a level 47 character it dealt 197 damage, I want the skill to always deal just one damage. (In case anyone is wondering why I want this skill, it's so that my character can take on insect swarms "like bees" which appear in groups of tens and twentys, and I want to give the player a choice between having enough MP to use the skill in certain shortcuts where swarms exist, or take the long way arround and not have to worry about MP. Having it deal 13 or more to everything is overkill, not to mention I don't want the player to concider using the skill on other low level monster groups, like slimes or bats.)