When you complete the first 10 levels and the Demon Lord, save and continue. Levels 11 to 100 are now unlocked. This basically repeats the first 10 levels until 100, but with stronger enemies and powered-up items. The new items are mixed about 50% with the old versions. You will still find things that were in the beginning of the game. The only changes in town are at the Guild where the quests have included all the monsters and new levels. Be prepared to see quests for enemies around level 800, and area searches around level 80 and up. Finding one appropriate to you may be difficult. To begin, you will only have access to levels 1 to 11, and after each 10 it repeats. Other than that, there does not seem to be anything new besides the items. All the Bosses, enemies, and levels still look the same, with the same requirements.
Use the following trick to acquire an endless amount of money with some patience. Do the following at the start of a new game before you make the actual five or so characters that you actually want to play with. The game allows you create up to twenty characters. Five can be in your active party. You can have the game automatically create characters for you -- keep pressing the button and it will randomly create characters and add them to the registry. All the new characters begin with basic equipment, weak armor, boots, head pieces, and a particular weapon according to their class. After the registry is full (the game will inform you that no more new characters can be created), you can view all of the characters in the registry's equipment. Here, you can remove all their items and stockpile them. You can then go to the trade booth and sell all the equipment. Since the game has weight requirements that determine how much your party can carry, use the stripped players to maximize your carrying capacity and minimize your trips to the trade booth. When all the automatically created characters' belongings are sold, delete them from the registry and repeat the process. This is a good way to get newly created characters the best gear in the shop immediately, ceause the only way to make money in the game is to sell items that you found in the dungeon, or take on jobs. It is possible to make 30,000g in an hour and a half with this trick.
To get combos, attack with weapons and spells of the same property. For example, have a caster use an elemental spell such as one of the fire ones that attack one opponent. Then, make sure a character is equipped with an elemental weapon such as a sword or knuckle with the same type. You can usually tell what type an item is by the name or by the resistance it gives. For example, fire resistance for a fire weapon. If you use both attacks at the same time, it has a random chance for the two characters to do a single attack, which does five to six times the damage compared to the non-combo regular damage. This works best on Bosses.
Compete in the Trial Battles to win rare items. You will receive one rare item for every ten battles you win. The best area for items is level 8 and each version until 98. Here, you can find over 70 items each time, and since the area is large and open, you can complete it with only twenty to thirty battles if you are good at dodging.
Always have one character with a high Trap Disarm ability. It can be frustrating clearing five areas almost getting to the Boss, then having a trapped chest send your entire party back to the surface.
Avoid the green rooms with the round computer inside. Once you are past level 5, the advantages they may provide are not worth the risk. The positive effects they give are few and far between the negative effects.
Turn the battle speed to maximum, and turn off battle animations. This will make most fights that usually last a few minutes end in about ten seconds. Only do this if you are quite strong and do not really care about strategy, but want to save time.