Angelfish is the bait to use to catch the Death Fish. Rare deathfish are usually found at night on cemetery lots, not. If Pets is installed, pets may visit the lot. Fishing spots repel Sims with the hates the outdoors trait. They attract Sims with the angler trait and are excellent for raising the fishing skill, and often contain rare fish spawners. Fog will surround the fishing spot, sort of like it does with graves. Fishing spot is a community lot assignment in The Sims 3. In Sunset Valley, the Death Fish can be found in the Graveyard pond from Midnight to Five in the morning. In short, prepare to be working on those four collections for a looooooong time. You have to have 10 fishing skill to fish up the Death Fish. On top of that, the microscope prints require fossil samples to finish and the elements require crystals and metals to be sent to the Geo Council so you’ll be needing multiples of almost every item. There’s really no way to improve those odds unless you have a treasure map to guarantee a MySims trophy so you quite literally just have to keep smashing your way through it until luck decides to come your way. With only a set number of spawners that refresh once a day and so many different items to collect from that finite number of rock spawners, your chances of actually getting the item you need when looking for those last few collectibles are much lower. For example, near the graveyard you can catch vampire fish, and at night between Midnight and 4am, the Death Fish, if your Sim has a high enough fishing.
Why are these called the Big Four? They are the most difficult collections to complete in the game, simply because all four collections come from the same rock spawners. You might want to save these collections (MySims trophies, fossils, metals, crystals) for after your Sim has a few of those coveted reward traits under their belts.