After you defeat the final Boss and the credits roll, save your game. When your desktop appears you will have new mail. Read the e-mail from Aura (which is unscrambled unlike her others). She tells you to go to Delta: Bursting, Passed Over, Aqua Field with Orca, who is now out of the hospital. Go to the bottom of the dungeon and Aura will give you the Book Of Daybreak, which allows you to use your Data Drain and Gate Hacking abilities again. After you log out, you will receive a message from Helba. She gives you member addresses for a lot of characters from .Hack//Sign, along with hers. The members addresses you get are for Helba (Wavemaster at level 99 with maxed out stats because she is a hacker), Tsukasa (Wavemaster at level 1), Subaru (Heavy Axeman at level 15), and Sora (Twin Blade at level 90). You will also receive another e-mail from Aura after receiving the Book Of Daybreak. You will get the Keyword Omega: Hidden, Darkside, Holy Ground. You will be accompanied by Elk for this dungeon; choose another character that has good strength. When you get to the last floor (there are fifteen floors and each contains many Data Bugs), you will fight a boss which resembles the guardian from .Hack//Sign and the Gate Hacked dungeons you went to earlier in the game. When you defeat the Boss, you will be able to choose Mia as a character again and receive two FMV sequences to watch on your desktop.
Put in a random keyword until you find a significantly higher level than yours (use Kite only) and make sure what element it is. Once you reach the server, use Speed Scrolls, Warrior Bloods, etc., and items such as Burning Oil, Well Water, or magics to raise element damage. Use a Hermit Blood on Kite and raise his element damage with an item/magic (whichever element is needed). Encounter an enemy with the opposite element and you will do heavy damage. After you level up, bring your other characters to the stage. You will notice that they also grew in levels by a bit. Use the same strategy (if needed) and raise their level as well. Also, as soon as Omega server opens enter Chosen, Hopeless as the first two parts of a keyword at that server. For the last part of the keyword, choose any one that has an element that your weapon is strong against. The monsters are not really that difficult. Your other party members that you did not bring will also get real nice experience gains. It is recommended that you take Wiseman and a lot of healing items. You can also use the keyword Chosen Hopeless on any server to get better gains
When you have the chance, I would suggest using Blackrose and someone who can heal. Give your two other party members 50 resurrects. You should have atleast 70. You should have a twin blade weapon that can do critcal damage. Such as Sora's Blades(But there are much better ones.) You could equip the Goblin Items. They do pretty good damage when doing Gobin King On Macha. BlackRose should get a powerful heavy blade weapon, and maybe some strong defensive equipment. Finally your other charcter. You should either have Elk(If he's usable),Balmung, or any others that heal. Have them first aid your attackers and you can beat the bosses anytime.(Cubia varies though
Look for characters from .hack//sign. If you cansee through them they're a ghost. Talk to them if you find one. They'll give you an item. To get you started go to Delta server and go to one of the alleyways and you'll find the character Mimiru as a ghost. Talk to her. She'll say a quote from .hack//sign. Next she will give you an item. Find the rest of her ghost only in towns in places such as Grunty Farm's, weapon shops etc. Other .hack/sign characters are involved. Renember to see the clips at Delta Hidden Forbidden Holy Ground first or you'll see no ghost characters.
If you press triangle while riding a Grunty, depending on what the Grunty is, it'll go toward and find something for you. In Omega server:
Rocker Grunty: Finds the dungeon for you
Woody Grunty: Finds the Spring of Myst for you
Noble Grunty: Finds Grunty Food for you
Aqua Grunty: Finds the dungeon
Other Grunty I haven't found yet: Finds the Spring of Myst
Noble Grunty: Finds Grunty food for you
Noble Grunty always finds the Grunty food, and there's always one Grunty to find the dungeon for you and one to find the Spring of Myst for you.
To get the highest level armor and weapons, go to Omega Chosen Solitary White Devil. This area's dungeon has no required fights and is a 2 floor dungeon.
The DVD that is included with the game has a secret section. It reveals secrets in the game. Enter the "Data" menu and highlight the ".hack Pro Trailers" option. Press Right to highlight a circular icon. Press X or Enter to view the secrets.
If you want to reduce the rate of infection quickly, go alone to a random field in Delta server. Use a Fairy's Orb and search for the portals, fight all the monsters you can. Since they'll be very low level monsters they'll be easy for you to defeat and won't be able to do much damage, but defeating them without Data Drain will still reduce the infection as much as a higher level monster would. Very useful before going to [Omega] Hidden Darkside Holy Ground or any time you need to get your infection rate down to get virus cores.