[1.4 Alpha] Bestiary Stars - tModLoader/tModLoader GitHub Wiki

The stars, or "rating", in the ingame Bestiary are controlled by a multitude of factors.
Below is the general formula (found in Terraria.ID.ContentSamples.GetNPCBestiaryRarityStarsCount()) that the game uses to determine the stars for any given npc, with a few exceptions:

1. Start with a default stars rating of 1.
2. Add npc.rarity to the rating.
3. Check the following conditions in order, adding to the rating only once:
   1. Is npc.rarity == 1 true? If so, add 1 to the rating.
   2. Is npc.rarity == 2 true? If so, add 1.5 to the rating.
   3. Is npc.rarity == 3 true? If so, add 2 to the rating.
   4. Is npc.rarity == 4 true? If so, add 2.5 to the rating.
   5. Is npc.rarity == 5 true? If so, add 3 to the rating.
   6. Is npc.rarity > 0 true? If so, add 3.5 to the rating. (This condition is true for any rarities above 5)
4. Is npc.boss true? If so, add 0.5 to the rating.
5. Calculate the sum of npc.damage + npc.defense + npc.lifeMax / 4. The stats used here are the NPC's stats in Normal Mode.
6. Using that sum, check the following conditions in order, adding to the rating only once:
   1. Is the sum greater than 10000? If so, add 3.5 to the rating.
   2. Is the sum greater than 5000? If so, add 3 to the rating.
   3. Is the sum greater than 1000? If so, add 2.5 to the rating.
   4. Is the sum greater than 500? If so, add 2 to the rating.
   5. Is the sum greater than 150? If so, add 1.5 to the rating.
   6. Is the sum greater than 50? If so, add 1 to the rating.
7. Cap the rating to 5, truncate it and then return it.

How can I add a custom stars rating to my NPC?

The dictionary ContentSamples.NpcBestiaryRarityStars stores the stars rating for all NPCs, including modded ones.

To manually set the rating for an NPC, set ContentSamples.NpcBestiaryRarityStars[type] = stars; in GlobalNPC.SetBestiary().
Example:

public override void SetBestiary(NPC npc, BestiaryDatabase database, BestiaryEntry bestiaryEntry){
    //Sets the rarity of ExamplePerson to 5 stars
    ContentSamples.NpcBestiaryRarityStars[ModContent.NPCType<ExamplePerson>()] = 5;
}

Setting an NPC's rating to less than 0 is treated as if the NPC's rating were 0.
Setting an NPC's rating to more than 5 is treated as if the NPC's rating were 5.