Tales of Phantasia [GBA]
After you have revealed Dhaos' Castle in the future, two new dungeons will be unlocked.
In the Treasure Room of the 21st level of Morlia, there is a blue button that you can press to reveal a warp for a new dungeon. Dungeon has 9 floors.
Morlia Mineshaft (Lower Levels)
After you have revealed Dhaos' Castle, head to 9th floor of the Morlia Mineshaft, now there will a new opening for 12 new floors (21 in all).
Whenever you play Ishitori with the Ishitori Master in Alvanista Castle, go first. Then Always bring down the amount of stones to whatever number is closest in this sequence
You will win every time.
There are several summons that can be obtained without going through the game, but doing certain other sidequests in the future after you have obtained the Tech Birds.
Get the Emerald Pact Ring from Gnome's Cave in the future and then make it to the 16th floor of Morlia Mineshaft, he is in a room filled with gas.
Get the Sapphire Ring from Undine's Cave and reach the 21st level of Morlia. He is in a room located in the south with gas.
Go to the Dwarven Ruins, obtain the Lapiz Ring there, and make it to the 9th floor to have a boss battle with Pluto/Brute.
The spirt of Darkness, Shadow
Go to Lone(Sylph) Valley and get the pact ring from the catacombs, then go to the cave of darkness to the southeast of Arlee.
The spirt of Light, Aska
Go to Alvanista and talk to the lady standing at south entrence, then go back to the time machine in Thor and ask for Aska to be released.
Battle Lv.3 (Maniac) Difficulty - Beat the game once.
Mini-Game - Let's Go Arche - complete the game once
New Game+ Mode - complete the game once
Pink Options in Title Screen - complete the game once
New Songs in Sound Mode - complete the game once (Japanese version only)