Instructions
Connect your Nintendo DSi to the Internet using the system's built-in WiFi connection.
Select the extra side quests from the "Dragon Quest IX" downloadable content menu.
Travel to Hermany and enter the house found on top of the hill.
Walk to the bookshelf and accept the new quest it offers.
Travel to Slime Hill and fight liquid metal slimes. You can reach Slime Hill by taking the Starflight Express to Angel Falls and heading east.
Defeat groups of liquid metal slimes with exactly three slimes each. You will need to defeat three groups of three to complete the quest and receive the metal slime shield.
Access the Alchemy system in the inn at Stornway and select the "Try Your Luck" option.
Combine the liquid metal shield with one orichalcum and six slimedrops to receive a liquid metal shield. Orichalcums drop from enemies including gem slimes, metal king slimes, and Greygnarl. Slimedrops are common drops from almost any kind of slime.
Create a metal king shield by combining your liquid metal shield with one orichalcum and one slime crown. Any variety of king slime can drop a crown.