Gimme a Trophy!
The I Want a Trophy! bill is unlocked from the beginning as soon as you unlock the Dark Assembly. However, it costs 50,000 Mana to propose, which means that you’ll have to wait until likely the postgame in order to even have a chance of trying for it, since Mana is quite easy to get then. The bad news is that it only has a 1% base chance for approval, so you’ll likely need to force it to pass.
There is only one preset stage that this can be done on, which is Death Promenade in the Spirit Interment area, but you can do it at any time. You will want to be sure to be able to be strong enough, where you can shrug off the attacks of the enemies on this map (Poison Vaccine helps, too). As you go through the stage, you will want to toss the Geo Symbols onto the panels as you pass them. At the very top of the map, the last symbol will be a Null one and once you’ve placed it, bring another character out of the Base Panel to destroy the very first symbol. If done right, you will get the trophy after the chain reaction is finished.
Making It Rain
When you fail to pass a bill in the Dark Assembly, one of the options you can do after it is to Pay Up. Finding a bill that requires 100 million HL can be a bit difficult, but one such bill is the one that unlocks the battle with Baal (Fight the Super Overlord!) in the postgame (costs around 139 million HL to pass with 99% approval rate).
A Minor Set Back
In order to get a Game Over in Disgaea, you typically need to make sure all of the characters you can deploy from the Base Panel are killed (default of 10). This can be easily done by creating 10 level 1 characters and have them get slaughtered on a later map. However, there is an easier way to get a Game Over without doing that. On the last map in Episode 4, you will receive a Game Over upon killing the neutral NPC. This works even on a retry after completing it for the first time (Back to Square One option in the Cheat Shop needs to be on).
The Water Feels Nice
The Hot Springs is one of the Mystery Rooms in the Item World and is completely random. Unlike previous entries, all of the Mystery Rooms can be found as soon as possible. In order to encounter more rooms and increase your chances, talk to the Rabbit NPC at Innocent Town and set the item route to Mystery Route.
This trophy is a bit confusing, as it’s not actually known what exactly counts as capturing enemies. Some people have gotten this from enemies surrendering, but others only received it after physically capturing them via the skill from the Capture Squad or Metallia’s Overload (she is DLC). The latter of the two options is more ideal and if you don’t get the trophy after physically capturing 100 enemies, then keep doing it until it pops.
Enemies that either surrender or are captured by the Capture Squad skill (or Metallia’s Overload) can be found in the Interrogation Room. One of the options, which doesn’t require you to interrogate them, is named " Make Citizen ." Do this for 100 different enemies to get the trophy.
Seasoned Rocket Rider
You will need to grind a bit for this trophy, as you need to discover 100 different Netherworlds via the Nether Research NPC. It might be easier to wait until the postgame to do this, as you can create a large group of high-leveled characters and then send them out to as many Netherworlds as possible. Note that you can only have 99 Netherworlds listed, so you will likely need to delete some as you’re doing this (select the Give Up option). You can keep track of your total by going to the Data Shop, then Netherworld Records and checking the 9th page.
Aren’t You Tired Of It…?
After completing Episode 4, you will unlock the Curry Shop. This lets you place in random items from your inventory that can be used to provide a buff for your characters on the next map. However, after creating a curry, do not use it and let it sit there. For every battle you complete, the curry will age by one day, so do 100 battles and come back to eat the curry, which will now last you for 100 battles before it runs out.
Netherworld Night Live
When returning to a base after completing a battle, you will sometimes notice that certain characters will have a "!" over their heads. Talking to them will trigger a conversation that is called a Skit. You will know when there’s a Skit available by a character’s portrait in the upper right corner, with "EVENT" listed under it. The best thing to do is always go back to your base after finishing a battle to check if there’s a Skit available or not. You only need to view 20 Skits to get this and there are a lot more than that in the game.
Switching to Overload
Certain characters in the game have access to a special skill that is only usable whenever their Revenge Gauge is full and they enter Revenge Mode. Overload skills can only be used once per battle, with Seraphina and Red Magnus being the first ones who have access to them. This is probably a trophy you will get as you naturally play through the game, as some Overloads are very useful.
This Calls For Teamwork
The description for this trophy is misleading, as it actually requires you to perform an Alliance Skill. These will unlock at the beginning of Episode 9 and require you to have two story characters next to each other in order to be able to perform the skill. The skills are marked with a "C" in the skill list for those characters that have them.