List includes crystals up to G11.
You can check this page too: Alchemy Crystals List - Mabinogi World Wiki
* Eabha sells the basic crystals (Clay, Fire, Water, Wind) for 100 gold (10 set) and 500 gold (50 set)
Crystal of Barrier (Barrier Spikes/Protective Wall): 3 Firewood + 1 Clay Crystal
Crystal of Life Drain: Mystic Pearl, along with the Crystals of the Four Elements at the Reactor. (Mystic Pearl can be fished out of the Abb Neagh lake.) You can also synthesize this using 1 Crystal of Arat and 1 Holy Water but the success rates are low (35% at Rank 6 Synthesis)
Crystal of Cloud (Rain casting): 10 Water Crystal + 10 Clay Crystal + 10 Wind Crystal + 1 Pollen (Pollen can be obtained from hitting the trees that are in the valley that is one map north of Tara, with a chance of getting this.)
Rock Golem Crystal: 1 Clay Crystal + 3 Low-grade Cuilin Rock (Can be made and summoned at Practice Rank)
Forest Golem Crystal: 1 Clay Crystal + 3 Common Cuilin Stone + 1 Base herb + 1 White Herb (Can be made at Rank 9, summoned at Rank C)
Sulphur Golem Crystal: 1 Clay Crystal + 2 Fine Cuilin Rock + 5 Sulphur (Can be made at Rank 5, summoned at Rank 9)
White Golem Crystal: 1 Clay Crystal + 2 Finest Cuilin Stone + 1 Silver Ingot (Can be made at Rank 1, summoned at Rank 5)
Crystal of Snowstorm (Frozen Blast): 3 Water Crystal + 1 Wind Crystal + 1 Snowball (Snowball can be obtained by hitting the snowman at Sidhe Sneachta hill)
Spark Crystal: 1 Royal Jelly + 1 Wind Crystal + 3 Fire Crystal (Royal Jelly can be obtained from hitting the trees that are in the valley that is one map north of Tara. Low chance of obtaining this from the tree, according to one of the wiki's comment.)
Fireball Crystal (Adv.Magic Crystal): Charged Fireball + 1 Fire Crystal
Ice Spear Crystal (Adv.Magic Crystal): Charged Ice Spear + 1 Water Crystal
Thunder Crystal (Adv.Magic Crystal): Charged Thunder + 1 Wind Crystal
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Mabinogi World Wiki