This is on level 3-13. If you need to unlock this level, you can find the map in level 3-2.
Level 3-2 (Map):
RURLD RDULD LULRD RDRDL DULUR LDRDR DLURD LDRDL DR
Level 3-13 (Artifact 6):
LULUL ULDRU LDULL LRRRR DULLL LDLUL ULULD LDL
(Thx for the catch of mistake: Aki2403)
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