Item Development, also called Item Synthesis, is a feature that first appeared in Hyperdimension Neptunia mk2 that allows the player to develop anything from items to weapons and accessories. You can develop new items by synthesizing ingredients. To develop an item, you need the ingredients and coinciding Plan, or Product Proposal. Also, in order to develop certain items, you need a certain Lily Rank. Item Development requires Plans and materials. Plans can be found in dungeons, looted from monsters, or purchased in the store, whereas materials can only be found in dungeons or by defeating certain enemies. Lily Rank also influences development due to some items requiring a specific Lily Rank between two characters in order to perform synthesis.
Hyperdimension Neptunia Re;Birth1 introduced an expanded version of Item Development called the Remake System. This system features plans that affect various mechanics of the game, including the battle system, dungeons, and more.
There are nine plan categories that are listed under Development:
- Accessory or Attachment
- Key Item