How to Get Each Summon

Chocobo- Start with it

Mist- Rydia has it after she rejoins your party

Titan- Rydia has it after she rejoins your party

Shiva- Rydia has it after she rejoins your party

Indra- Rydia has it after she rejoins your party

Jinn- Rydia has it after she rejoins your party

Asura- To get the Asura summon, go to the cave of summoned monsters, which is in the underground west of the dwarf castle. Work your way through the cave by using the "Float" spell to go over the glowing dots. Once you reach the town of summoned monsters, go into the library and use the teleport. Talk to Asura then begin to fight her. The easiest way to beat her is have Rosa use the "Wall" spell on Asura so her cure attacks are used on you and not her. If you use the "Wall" spell on her DO NOT use any other magic on her. Just attack. Once you beat her, she will give you the ability to call her. Now talk to Leviathan, who is next to her.

Leviathan- See how to get to Asura for the way to Leviathan. Once you reach Leviathan engage in battle. Have Rydia use Ice3, Edge use Blitz, Cecil attack, and Rosa use Cure 2 or 3. Continue doing this until Leviathan is defeated. After he is deafeated he will grant you the ability to call on him.

Odin- To get the Odin summon you first have to get the Asura and Leviathan summons. Once you get those summons go to Baron. After you get to Baron, go down to the basement on the right side of the castle. You will meet the king and then he will challenge you. You have to be pretty quick in defeating him. Have Edge use Blitz, Rydia use Lit3 or Indra, Rosa attack, and Cecil attack. If you attacked him fast enough and managed to kill him he will give you the ability to call him.

Slyph- To get the slyph call you need to go to the Slyvian Cave in the northwestern part of the underground. Once inside use the "Float" spell to go over the glowing dots. After you work your way through there you will find Yang and about 4 slyph faries. Go up to Yang and try to talk to him. He won't say anything. Now, go back to Fabul and tell Yang's wife about him. She will give you a frying PAN. Go back to where Yang was and hit him with the PAN. He will wake up and will want to go with you. The slyph faries won't let him go because he needs rest. Instead, they offer to help you by giving you the ability to summon them.

Bahamut- After you get to the moon, go to the cave that is the center of a rock circle. Once inside get the Samurai Armors and equip them (they will help once you fight Bahamut). While you make your way through the cave you will fight 3 Behemoths. Make sure your health and magic is high before you fight them. After you kill all of the Behemoths you will find yourself at the end of the cave and will fight Bahamut. To defeat Bahamut, have Cecil attack, Edge attack, Rosa use cure, and Fusoya and Rydia use wall on each character. When Bahamut uses MegaNuke it should reflect off of your party and hurt him. Repeat the process until Bahamut is defeated.

Imp- Fight Imps, Imp Captains, and Trickers

Bomb- Fight Bombs, Grenades, and Balloons

Mage- Fight Mages