The Izmit Cave is your first dungeon. It's a straightforward cave with a few branching paths. The monsters here include Bunicorns, Healslimes, and sometimes a Metal Slime (though rare). Focus on defeating all enemies to gain experience. The Healslimes can be annoying, as they heal other monsters, so prioritize them. Navigate through the cave, collecting any treasure chests you find. You'll eventually reach a deeper section where you'll find the missing children and the boss.
Recommended Level: 5-6. Ensure Ragnar has the best equipment available (Copper Sword, Leather Armor, Leather Shield). Use Medicinal Herbs when your HP drops below 20. The boss of this cave is a simple fight, but don't underestimate it. Keep attacking and heal when necessary. After defeating the boss, the children will be rescued, and you can return to Burland to report your success to the King, concluding Chapter 1.