GUIDE
YELLOW POINT = low level bosses (tapisan equipment / yellow stones)
ORANGE POINT = mid level bosses (unik equipment / violet stones )
TRED POINT = high level bosses (elite equipment / reds stones )
Misty Marsh
Gobi Desert
Dark Marsh
Icyland
Island
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Although its not totally correct, but you still could refer as pin point. It’s found that bosses appear in 1 hour or 30 minutes time, but it’s random