First of all, I am not sure at this time of post whether other versions outside the Japanese one received patch 1.02. If you have been following guides that promotes Dark Water, I am afraid to say that it no longer works. In 1.02, I think the bosses' resistances were increased to the point where Dark Water is impossible to land.
So obviously I have been following those guides (including Japanese ones) without considering that 1.02 screwed all of them. With the absence of Dark Water, this means that you cannot lame out bosses with Sleep/Poison effects. It also means that you other end game items need to be stronger.
For end game equipment, this guide still works. The most important part is getting as high defense as possible, as well as at least 1 Shadow band on Totori. The Shadow Band is, of course, to be used in conjunction with a very good Dimension Egg. You will get 6 turns in total if your Egg is built right. Also, I find that on Totori, it does not matter if the Shadow Band has high quality (higher quality Bands drain more health per turn) since it does not kill. It's nice to have it as low quality as possible, but not THAT neccecery.
For characters, it does not really matter as long as they are well-equipped and around level 45-ish. I manage to beat the bosses with Sterk and Mimi, which shows that you don't really need Rorona and abuse her ability to use items. All you really need your party to do is to defend Totori as much as possible. If Totori dies, you will lose.
Now let's talk items. I won't go so much into details on how to transfer traits because that's the fun part of the game. All items list are more or less equally important so try not to compromise them.
Elixir
This item is what keeps your party alive and healthy. You cannot compromise this item at all in my opinion. Drache's guide's Elixir covers it perfectly so I'm just reiterating it. Effects needed are HP Recovery from having it made high quality (so that Shadow Band isn't that painful), HP Healing L from a high quality Nectar, and MP Recovery L from a LOW QUALITY Sage Herb. The MP Recovery is really important, I cannot stress that enough. I personally made one without it and it was hell wasting turns to drink Mind Waters and having my party members out of mana after using their skills a few times. MP Recovery ensures that your party will ALWAYS be able to use their skills, and ensures that Totori do not waste TONS OF TURNS drinking Mind Water JUST to duplicate stuff (especially Dimension Egg).
Traits are also the same as Drache's guide. Healing Essence from Forest Dew, so that it automatically revives your members should they randomly die for being unlucky (it happens). Cure-All will naturally be there with Sage Herb, so that it heals everyone. Also Source of Life from Bless Stone to restore LP. Having low LP is pretty much one of the causes of death due to the reduction of defense. And of course, what else to spend on the last two traits? Simply, Effect Boost L and Rank Boost L.
Totori Brunch
This item is especially useful if bosses hold the threat of one-shoting your characters. Most (if not all) the bosses notoriously tries to lower your characters' attack and defense by a good amount. Feeding them this Totori Brunch would mostly likely negate the effect. Again, not as essential as the other items, but still occasionally useful when all else fails.
Totori Brunch
This item is especially useful if bosses hold the threat of one-shoting your characters. Most (if not all) the bosses notoriously tries to lower your characters' attack and defense by a good amount. Feeding them this Totori Brunch would mostly likely negate the effect. Again, not as essential as the other items, but still occasionally useful when all else fails.
Effects are:
Final Strike L
Rank Boost L
Beginners OK
Lone Slayer L
Boost Effect L
Dimension Egg
You probably heard this item tons of times. With Shadow Band, this essentially gives the user 6 turns (I confirm that it's 6) at the expense of depleting all available mana (this is where and should be the only time Mind Water comes in). It lasts for 2 rounds, so on the second round you don't have to waste 2 turns duplicating Dimension Egg and then drinking Mind Water. You might be able to compromise this by giving it lousier traits somewhat, ending up with less turns but still able to function. Keep in mind that less turns might give you more trouble against bosses that regen or heal. For the purpose of this guide, I'm using my 6 turns Dimension Egg.
Effects are:
Effect Boost L
Boost Effect L
Rank Boost L
Final Strike L
Lone Slayer L
Himmelstein
Othogalaxen bosses have retarded elemental resistances so N/A supposedly won't work on them (unless they changed their resistances this patch which I didn't check). Either ways, this bomb is non-elemental damage so patch or no patch, this is a reliable source of damage. I made 2 versions of this, one to debuff enemies (so that I don't really need to make Magic Chains like some guides do), the other for pure damage. The pure damage Himmelstein should be doing around 2000 damage after debuffing enemies and bugging yourself with Ether Ink. It can critical for even more!
For the damage Himmelstein, effects are:
Beginners OK
Rank Boost L
Effect Boost L
Lone Slayer L
Giant Slayer +
For the debuffing Himmelstein, effects are:
Soul Steal
Giant Slayer +
Rank Boost L
Effect Boost L
Strength Steal
Ether Ink
This item just boosts all your items when you use them! To top it off, it is relatively easy to make a good one. You just have to get it to a quality where it has the Item Effect + trait. It's an easy to make item which you spend 1 turn using which increases your Himmelstein damage by around 400 (this of course depends on how good your Himmelstein is in the first place). You can live without it though.
Mind Water
Simple item. It's best, of course, to make it such that it has MP Recovery XL but as long as your Elixir is giving MP too, MP Recovery M is enough since you are going to use it only when you totally run out of MP (after using Dimension Egg, or if you miscalculated and don't have MP to use duplicate). Wholesale THIS. You are not going to duplicate this. Wholesale and buy. Bring a bunch to Orthogalaxen. You don't really have to give it crazy effects and stuff so don't waste too much resources working on it.
Strategy
With these items, the strategy for all bosses is pretty much the same, with only a few minor notes to take care of.
Basically your team members will keep using their most damaging skill on the boss(es). ALWAYS choose to protect Totori. If Totori dies, the team is as good as dead (unless the boss is down to a pixel). I repeat, ALWAYS protect Totori, if Totori dies, party dies.
So obviously the main focus of the fight is Totori herself. With Dimension Egg and Shadow Band, you will have 6 turns. The first turn goes something like this:
1) Ether Ink
2) Duplicate Dimension Egg (this will wipe your MP)
3) Mind Water (this will restore some MP)
4) Duplicate Elixir (this will heal the whole party, give them regen and give tons of MP)
5) Duplicate Debuffing Himmelstein (this will weaken your foes by a ton)
6) Duplicate Himmelstein
Then the second turn goes something like:
1) Duplicate Elixir
2) Duplicate Himmelstein
3) Duplicate Himmelstein
4) Duplicate Himmelstein
5) Duplicate Himmelstein
6) Duplicate Himmelstein
Then third turn goes something like:
1) Duplicate Dimension Egg (this will wipe your MP)
2) Mind Water (this will restore some MP)
3) Duplicate Elixir (this will heal the whole party, give them regen and give tons of MP)
4) Duplicate Himmelstein
5) Duplicate Himmelstein
6) Duplicate Himmelstein
After doing it awhile, you will get used to the strategy. Then you can start being flexible about the decisions like maybe throwing an extra Himmelstein, or using Totori Brunch, etc. BASICALLY the big picture is:
1) Debuff enemy (Debuff Himmelstein)
2) Buff with Ether Ink
3) Dimension Egg
4) Regain mana
5) Bomb the crap out of the boss
6) Go back to step 3 and repeat
This will more or less work for ALL the Orthogalaxen bosses. The only problem I had was Blood Element, where she has the potential to wipe my team easily. If I survived her first round, I did the following instead for my first turn:
1) Duplicate Totori Brunch (on first member)
2) Duplicate Dimension Egg (this will wipe your MP)
3) Mind Water (this will restore some MP)
4) Duplicate Elixir (this will heal the whole party, give them regen and give tons of MP)
5) Duplicate Debuffing Himmelstein (this will weaken your foes by a ton)
6) Duplicate Totori Brunch (on second member)
This will ensure that her attack will be reduced and your party member's defenses will be greatly increased to the point where her attack can potentially (for my case) deal 1 damage per hit. After doing so, it's pretty much smooth sailing.
Well that's all I have to share. Good luck!
Final Strike L
Rank Boost L
Beginners OK
Lone Slayer L
Boost Effect L
Dimension Egg
You probably heard this item tons of times. With Shadow Band, this essentially gives the user 6 turns (I confirm that it's 6) at the expense of depleting all available mana (this is where and should be the only time Mind Water comes in). It lasts for 2 rounds, so on the second round you don't have to waste 2 turns duplicating Dimension Egg and then drinking Mind Water. You might be able to compromise this by giving it lousier traits somewhat, ending up with less turns but still able to function. Keep in mind that less turns might give you more trouble against bosses that regen or heal. For the purpose of this guide, I'm using my 6 turns Dimension Egg.
Effects are:
Effect Boost L
Boost Effect L
Rank Boost L
Final Strike L
Lone Slayer L
Himmelstein
Othogalaxen bosses have retarded elemental resistances so N/A supposedly won't work on them (unless they changed their resistances this patch which I didn't check). Either ways, this bomb is non-elemental damage so patch or no patch, this is a reliable source of damage. I made 2 versions of this, one to debuff enemies (so that I don't really need to make Magic Chains like some guides do), the other for pure damage. The pure damage Himmelstein should be doing around 2000 damage after debuffing enemies and bugging yourself with Ether Ink. It can critical for even more!
For the damage Himmelstein, effects are:
Beginners OK
Rank Boost L
Effect Boost L
Lone Slayer L
Giant Slayer +
For the debuffing Himmelstein, effects are:
Soul Steal
Giant Slayer +
Rank Boost L
Effect Boost L
Strength Steal
Ether Ink
This item just boosts all your items when you use them! To top it off, it is relatively easy to make a good one. You just have to get it to a quality where it has the Item Effect + trait. It's an easy to make item which you spend 1 turn using which increases your Himmelstein damage by around 400 (this of course depends on how good your Himmelstein is in the first place). You can live without it though.
Mind Water
Simple item. It's best, of course, to make it such that it has MP Recovery XL but as long as your Elixir is giving MP too, MP Recovery M is enough since you are going to use it only when you totally run out of MP (after using Dimension Egg, or if you miscalculated and don't have MP to use duplicate). Wholesale THIS. You are not going to duplicate this. Wholesale and buy. Bring a bunch to Orthogalaxen. You don't really have to give it crazy effects and stuff so don't waste too much resources working on it.
Strategy
With these items, the strategy for all bosses is pretty much the same, with only a few minor notes to take care of.
Basically your team members will keep using their most damaging skill on the boss(es). ALWAYS choose to protect Totori. If Totori dies, the team is as good as dead (unless the boss is down to a pixel). I repeat, ALWAYS protect Totori, if Totori dies, party dies.
So obviously the main focus of the fight is Totori herself. With Dimension Egg and Shadow Band, you will have 6 turns. The first turn goes something like this:
1) Ether Ink
2) Duplicate Dimension Egg (this will wipe your MP)
3) Mind Water (this will restore some MP)
4) Duplicate Elixir (this will heal the whole party, give them regen and give tons of MP)
5) Duplicate Debuffing Himmelstein (this will weaken your foes by a ton)
6) Duplicate Himmelstein
Then the second turn goes something like:
1) Duplicate Elixir
2) Duplicate Himmelstein
3) Duplicate Himmelstein
4) Duplicate Himmelstein
5) Duplicate Himmelstein
6) Duplicate Himmelstein
Then third turn goes something like:
1) Duplicate Dimension Egg (this will wipe your MP)
2) Mind Water (this will restore some MP)
3) Duplicate Elixir (this will heal the whole party, give them regen and give tons of MP)
4) Duplicate Himmelstein
5) Duplicate Himmelstein
6) Duplicate Himmelstein
After doing it awhile, you will get used to the strategy. Then you can start being flexible about the decisions like maybe throwing an extra Himmelstein, or using Totori Brunch, etc. BASICALLY the big picture is:
1) Debuff enemy (Debuff Himmelstein)
2) Buff with Ether Ink
3) Dimension Egg
4) Regain mana
5) Bomb the crap out of the boss
6) Go back to step 3 and repeat
This will more or less work for ALL the Orthogalaxen bosses. The only problem I had was Blood Element, where she has the potential to wipe my team easily. If I survived her first round, I did the following instead for my first turn:
1) Duplicate Totori Brunch (on first member)
2) Duplicate Dimension Egg (this will wipe your MP)
3) Mind Water (this will restore some MP)
4) Duplicate Elixir (this will heal the whole party, give them regen and give tons of MP)
5) Duplicate Debuffing Himmelstein (this will weaken your foes by a ton)
6) Duplicate Totori Brunch (on second member)
This will ensure that her attack will be reduced and your party member's defenses will be greatly increased to the point where her attack can potentially (for my case) deal 1 damage per hit. After doing so, it's pretty much smooth sailing.
Well that's all I have to share. Good luck!