It is best to approach gathering any Summon items that you are missing once you have reached the endgame/the Moon, in order to make the battles quick and easy.
Stick on a Spotify playlist or YouTube in the background and mindlessly farm away!

As of a recent update, the Siren item can now be purchased from the merchant in Hummingway Abode on the Moon for 3000 Gil apiece, so they are now far easier to restock if need be.

Remember that you then need to use the Summon items from your inventory in order for Rydia to learn them.

If the Achievement doesn't pop up for you right away after learning the 4 spells, finish up another random encounter and it will unlock for you then.

If I have made any mistakes or you know of any alternatives methods, let me know in the comments!

The Goblin item can be dropped by both Goblin (Overworld outside Baron among many others) and Lil' Murderer (Lunar Subterrane) and is probably the first of the items you will manage to acquire.

The easiest location to farm the item is on the Overworld right outside the entrance to Mt. Hobs. Between 6 and 9 Goblins spawn at once quite regularly, and are easily disposed of even in the early game.

I'll update with screenshots soon!

Cockatrice can drop from all variants of the creature, but by far the easiest method of farming them is to use the Siren item on the Mysidia continent. I had positioned myself around the middle at the forest section at the time of the screenshot.


This will always give you a battle against 3 Cockatrice alongside a Zu. Rinse and repeat until you get the item.

Mindflayers are best found in Lodestone Cavern in groups of 2, or alongside a Cait Sith and an Ogre, thus appearing quite commonly.

Using a Siren on B1 and B2 will always bring you into a battle against 2 Mindflayers, so this is by far the quickest method for farming the item.
(Thank you to Fox Kenichi and Pure Mind Games for confirming this!)

I'll update with screenshots soon!

The Bomb item is dropped by both Balloon and Dark Grenade on the Lunar Surface. Take note that the item does NOT drop from regular Bomb enemies and other variants.

Sadly, we can't use a Siren to force ourselves into a battle with these enemies, so our best option is the grind random encounters, either on the Lunar Surface between the west and east passages, or in the west passage itself. The group of enemies we're looking for is comprised of 2 Balloons and 2 Dark Grenades.

Inside the west passage, you can also find battles with 3 Dark Grenades alongside an Abyss Worm, so this is the better of the two areas assuming you can handle the slighter harder battles.


A good auto-battle setup is as follows, and will allow you to breeze through the other sets of enemies and regularly heal yourself a bit:

Cecil, Kain and Edge - Attack
Rosa - Pray
Rydia - Thundara/Thundaga on all enemies

Thundara/Thundaga will easily get rid of any flan enemies that haven't perished in your initial physical assault.
If you're at it a while, you may occasionally need to use a Tent to heal up Rydia's MP and any other damage taken. This is also a good spot to grind some levels for the final dungeon while searching for the item.


Occasionally, the enemies will drop the Bomb Fragment or Bomb Core items, just to get you overly excited for a millisecond.
To misquote Ben Kenobi, "These aren't the drops you're looking for."

Happy hunting!