Unlimited Mid Tonics
Mid tonics are four times more powerful than regular tonics and are sold for 1,000 gold. In order to get unlimited mid tonics, travel to the Dark Ages period in the game, where you are captured and imprisoned. Escape the jail by rattling the iron bars and defeating the lone guard. Afterward, exit to the bridge area on the right. There will be three guards here, each of whom drops a mid tonic when defeated. After dispatching these foes and collecting the tonics, leave the room and re-enter. The guards will be back and can be defeated once again for more potions. Repeat this as desired.
Unlimited Shelters
Shelters are purchased for 4,000 gold and allow you to fully regenerate health and save your game file. You can collect an unlimited number of shelters by travellng to Guardia Forest in 600 A.D. Find the moving bush in the forest and talk to the monster that appears from it. This monster will drop a shelter as it flees. Leave the forest and return, and the monster will drop another shelter. Repeat this until you reach your fill.
Unlimited Power Tabs
Power tabs are dropped by enemy monsters. You can boost a character's stats by equipping a power tab to its inventory. In order to receive unlimited power tabs, go to the Black Omen. Make sure Ayla is in your party and that she can cast the charm spell. Fight the turbo monster in this area by casting charm. The turbo monster will drop a power tab. After defeating it, leave the room and re-enter to fight it again and collect additional power tabs until your inventory is full.
Free Clothes
In order to get free clothes, including helms, vests and mail, go to Lucca's house in 1000 A.D. Talk to Lucca's father, Taban. Each time you talk to Taban, he will offer you a different item of clothing. You can leave 1000 A.D. and come back to receive more of each item until you are able to equip your entire party in free clothing.