The best helmet in "Dragon Quest 3: HD-2D Remastered Edition" is a special achievement trophy in the game, and the requirement for this achievement is to obtain the Helmet of Light. If you want to do this achievement, you can After getting Dad's helmet in the Mu'ol incident, the conversation with the NPC in the swamp cave triggers blue metal-related content.
How to get the best helmet achievement in Dragon Quest 3 Remake
The best helmet
Get the Helmet of Light
[Ranseer] Go up and enter the navel of the earth. On the second underground floor, take the stairs in the upper right corner to enter the third underground floor. Then take the path below to the end and come to the fourth underground floor. Investigate the stones on the wall, and then go to In the [Swamp Cave] in the south of the island where [Myra] is located, talk to the character in the lower right corner to get information about the blue metal. Then go to [Leibei] to talk to the old man to get the second important item "Magic Ball". Return to [Earth's Navel], go to the 4th underground floor and blow up the wall to get the important item "Blue Metal"
[Muor] Enter the prop shop on the upper right through the side door on the right. After the plot, go to the second floor to talk, then return to the first floor to get the equipment "Ortega's Helmet"
Teleport to the [Dwarf Ancestral Hall] (just to the left of the Shoal Ancestral Hall), automatically trigger the plot, and get the equipment "Helm of Light"