Which items make Monster Crystals

Here is a list i made to create monster crystals fast:

Basic Monster Crystal I : 100 drops of a lvl 32 Ligator,
Warning Street: The Swamp of Despair I
Basic Monster Crystal II : 100 drops of a lvl 52 Croco,
Warning Street: Dangerous Croko I
Basic Monster Crystal III : 100 drops of a lvl 63 Slimy,
Singapore: Ghost Ship 2

Intermediate Monster Crystal I : 100 drops of a lvl 73 Homunculus,
Zenumist Research Institute: Lab - Unit 202
Intermediate Monster Crystal II : 100 drops of a lvl 88 Red Kentaurus,
Leafre: The Area of Red Kentaurus
Intermediate Monster Crystal III : 100 drops of a lvl 93 Spirit Viking,
Ludibrium: Warped Path of Time 4

Advanced Monster Crystal I : 100 drops of a lvl 105 Jr. Newtie,
Leafre: Destroyed Dragon Nest
Advanced Monster Crystal II : 100 drops of a lvl 113 Skelosaurus,
Mini Dungeon: The Restoring Memory
Advanced Monster Crystal III : 100 drops of a lvl 121 The Pupil of Oblivion,
Time Road: Path of Oblivion I

Ofcourse, when you are making a lvl I Monster Crystal, there is a chance that you will make a lvl II or III Monster Crystal.