Battle Mode

Battle Mode is an option in both Golden Sun games. It is where players can battle and practice different strategies against monsters and bosses from the game and against friends with use of a link cable. No coins or EXP are earned in Battle Mode. With this mode you can use all the items and Djinn that you currently have in your posession. All battles take place in a colosseum setting similar to Colosso and play the standard Battle Theme.

Lobby
In the Lobby you can talk to all the Adepts you currently have in your party. Other than that there are just a bunch of NPC's you can talk to. You are not allowed to use Psynergy or allowed to save while you are in the lobby, with the exception of battle records which get automatically saved by the woman at the counter. But if you talk the lady in the lower left while holding a shoulder button in Golden Sun: The Lost Age you can listen to the game's Sound Test option.

Monster Battle
The Monster Battle mode is initiated when you have no link cable inserted into the console. You must talk to the woman at the counter and she will tell you to stand in the white circle when you are ready. With Monster Battle you can battle any monster you have already battled in the game, including boss battles, but you are not able to battle Djinn. Enemies from Golden Sun will not appear in The Lost Age and vise versa. While battling any monster you are not allowed to run. Any items used in battle will automatically be returned to the party as soon as they are done battling and choose to quit. Basically put, it's the only place where Isaac can square off against Poseidon. It can also be seen as a true test of endurance seeing as how you can easily get pitted against Dullahan 10 times in a row.

An oddity in the Monster Battle Mode occurs if you play on Easy Mode in The Lost Age: all of your enemies will be far stronger to begin with, although this evens out the farther you get in the game. It's very easy to be downed by a simple Ruffian though and could throw off players thinking an easy win is in store.

Link Battle
With the Link Battle option you may battle a friend with a copy of the same game to see who's better; however, you cannot link the original Golden Sun to The Lost Age. All of your battle wins will be displayed on the wall. Other than for bragging rights it serves no real purpose.