The best place to farm Silithid Heart is Thousand Needles, where Silithid Hive Drone (level 33-34) drops it at 80.0%. That is the vanilla 1.12 chance, not yet confirmed in Forever. 4 sources are ranked below by drop chance.
Best zones:

- Silithid Hive Drone 64.8, 86.0
- Silithid Searcher 71.2, 85.5
- Silithid Invader 64.5, 85.8
- Silithid Ravager 68.4, 82.3
All sources, by drop chance:
| Source | Level | Zone | Spawns | Side | How | Drop% | Map |
|---|---|---|---|---|---|---|---|
| Silithid Hive Drone(quest) | 33-34 | Thousand Needles | 14 | Drop | 80.0% | map | |
| Silithid Searcher(quest) | 32-33 | Thousand Needles | 9 | Drop | 80.0% | map | |
| Silithid Invader(quest) | 34-35 | Thousand Needles | 8 | Drop | 80.0% | map | |
| Silithid Ravager(rare) (quest) | 36 | Thousand Needles | 1 | Drop | 80.0% | map |
Needed for:
Quests:
Drop% is the rate recorded in Forever once a source has been looted ten times; a greyed figure is the vanilla 1.12 chance from the world data (vanilla reference — from the 1.12 world data, not yet confirmed in forever). Spawns counts the source's spawn points in the world data. "Side" names which side can kill the NPC when the other finds it friendly. The lead picks the best chance among sources that are not a rare spawn and have at least three spawn points.