Seed of skill
A Seed of Skill is a one-time use item that increases the skill point total of whoever eats it by 5. It only appears in later Dragon Quest installments that use a point-allocation skill system.
The seeds can be found in an overworld chest near Pickham, in pots/cabinets in Neos and Empycchu, and may be purchased once from a midnight shop in Arcadia. A small selection of normal monsters drop them as rare items; Solaris, Great trolls, and Crocodogs specifically, with a 1/64 chance for each. Furthermore, all forms of the Lord of Dragovians have a 1/8 chance to drop the spermatophyte.
Regardless of which monster the player goes after, it is 'strongly recommended to make use of Yangus' Stainless Steal Sickle; the acquisition chance will be cut in half, but being able to attempt stealing multiple times in one battle is well worth the trade-off.
Unlike in Dragon Quest VIII, characters can generally gain more skill points through revocation so these seeds aren't as useful.