The metal slime in "Dragon Quest 3: HD-2D Remastered Edition" is a unique special monster in the game. If you want to cause damage to the metal slime, you can use ordinary weapons to attack. This Meaning you can only choose basic attacks and hope to hit them.
How to damage metal slimes in Dragon Quest 3 Remake
The only way to deal damage to metal slimes is through normal weapon attacks, which means you can only choose basic attacks and hope to hit them. Metal slimes have very high defense and agility, which means they will dodge your attacks most of the time, and even when attacks hit, they usually only deal 1 point of damage. While Metal Slime's agility is extremely high, this stat reaches a level that no character can easily reach unless you come back later in the game.
If you can hit a critical hit, the damage will be greatly increased, and the metal slime can be defeated instantly. Therefore, use the rogue's "Assassination" skill to try to maintain the frequency of critical strikes.
Metal slimes have a high chance of escaping each round, so you need to prioritize attacking them once you spot them. Metal slimes are completely immune to all magic and item effects, so don't waste time trying to use magic or items and just start attacking. Skills like "Call of the Wild" can attack multiple times, which is useful when facing only one metal slime, but if there are multiple metal slimes, it's usually better to focus fire on one so that your teammates' AI can focus. Attack the same target and defeat it before it escapes.
When you encounter a metal slime, just attack it with the basic attacks of the entire crew and hope it doesn't run away, because there's not much else you can do. Other monsters need to be watched out for, lest they defeat your party and cause you to lose experience. Therefore, it may be necessary to have your healers keep the party's health up while focusing on Metal Slime defeat first.