Hint: Unlimited Chips & SP
At London city, go to the casino (slum area). Use a save and load method, and play roulette by betting 1000 chips for the first 9-12 numbers which you can earn around 24000-26000 chips if you win. The chances is roughly 1/3 to 1/4. Quit casino and save after you win. Naturally, if you lose, reload your last save. Repeat that and you can earn unlimited casino chips.

After you obtained all the goodies in the casino presents, you can sell that item in casino which recovers 50% of your HP and EP at the shop next door. You can only carry 9 on you at a time. So you will have to buy them from casino using chips and sell them at the shop. You can get 5400 TB for 9 of them. Repeat the step above and you can have unlimited money and unlimited SP because SP can be purchased at the shop.

Hint - Omega Tactics
Omega is the final boss in the holy beast shrine At first it seems impossible to kill Omega with him having 99999 hp and ep but he is rather easy to defeat with a golem that has a special attack that takes a % of damage. I used Sebastian sniper shot. The first few shots with him did about 35000+ damage. Other golems you can use is Raiko or Samurai. Lastly, keep your members out of his God Scream