Muffler

Source: npc/quests/first_class/tu_sword.txt

1. Go to swordman trainer Shurank at izlude_in,82,163.
2. In his training chain, level Bash to 10.
3. On skill check, he confirms Bash mastery and advances the stage.
4. Reward branch uses getitem 2503, 1.
5. That item is Muffler.