The Anglerfish is one of the rarest fish in The Sims 4, but you can catch it with the Base Game. Your Sim needs to reach Fishing Level 7 before the Anglerfish becomes available.
You can level up Fishing by fishing at any available fishing spot.
If you’re using cheats, enter: stats.set_skill_level Major_Fishing 7
The best places to look for Anglerfish are Sylvan Glade and Forgotten Grotto. Anglerfish can also be caught at the Willow Creek Park fishing spot.
Sylvan Glade is the easiest option. You don’t need an Expansion Pack to access it, and the area contains fishing spots where Anglerfish can appear.
Find the Mysterious Tree in Willow Creek. Your Sim needs to interact with the tree several times until the Explore option becomes available.
Enter the tree and follow the exploration prompts to reach Sylvan Glade.
Once you’re inside Sylvan Glade, look for the fishing areas around the waterfall and pond.
Use medium-sized fish as bait.
Once your Sim reaches Fishing Level 3, you can select Fish with Bait. Use a medium-sized fish such as Koi, Bass, Salmon, or Catfish as bait.
You don’t need to obsess over finding one particular bait item. The important part is using the appropriate medium-fish bait category.
At Fishing Level 3, your Sim can use Examine Water at fishing spots. This lets you study the water and identify the fish available at that location.
This is one of the most useful tricks when you’re completing the Fish Collection. Instead of blindly fishing at random locations, examine the water first and see what the spot contains.
Anglerfish are classified as Rare, so using the correct bait and fishing location doesn’t guarantee an immediate catch. You may need to keep fishing for a while.
Forgotten Grotto is another good option for Anglerfish. It's the secret area accessed through the mine entrance in Oasis Springs.
The catch is that accessing Forgotten Grotto requires Level 10 Handiness to break open the entrance.
So, unless your Sim already has high Handiness, Sylvan Glade is considerably more convenient.
Fishing is a skill, so anything that helps your Sim stay productive while fishing is useful. A Focused mood is particularly helpful when you’re trying to level Fishing and get through a long fishing session.
You can also use the Fishing skill interactions available at higher levels. At Level 9, for example, your Sim unlocks Angle for Big Catch.
However, don’t confuse this with a guaranteed Anglerfish catch. It’s a fishing advantage, not an Anglerfish cheat.