It's a pain dealing with the whole summons sometimes, so it's useful when making rainbow items to know alternate sources of the shiny materials. They can be obtained by disassembling certain rare items, which in turn can be stolen by Kid or Fargo from the monsters listed below.
|Shiny item||Location||Acquire from||Item acquired|
|Shiny Dew||Another Viper Manor Sewer||Steal from SpearFisher||Antiviral Cap|
|Shiny Soot||Another Fossil Valley||Steal from ShadowCat||Daemon Charm|
|Shiny Ember||Another Pyre Cave||Steal from CatBurglar||Poultice Cap|
|Home Pyre Cave||Steal from LavaBoy||Flame Charm|
|Shiny Leaf||Home Gaea's Navel||Steal from PreyMantis||Forest Charm|
|Another Gaea's Navel||Steal from PreyMantis||Forest Charm|
|Shiny Salt||Another Terra Tower||Dropped by Myxomocete||Angel Charm|
|Shiny Sand||Another Terra Tower||Dropped by Whoot||Earth Charm|
|Another Gaea's Navel||Steal from Prehysteric||Earth Charm|
|Another Earth Dragon Isle||Steal from YellowBelly||Earth Charm|
To forge rainbow items, defeat the black dragon the hard way, then go to Home Marbule after it reopens (random: the demihuman at the entrance will give you the FullRevival element when Marbule reopens); find the man in the cave where Black Dragon was, who will sell a Master Hammer to you. Equip on Zappa, and with Zappa in party head to Another Termina and chat with the Zappa there. Most rainbow items require a rainbow shell and one of each shiny material above.