For this Challenge, you will need to kill Spiderants, and it doesn't matter which ones. There are a few places where you can farm kills, such as the Nether Hive area of Caustic Caverns.
- Rank 1: Kill 10 Spiderants
- Rank 2: Kill 25 Spiderants
- Rank 3: Kill 75 Spiderants
- Rank 4: Kill 150 Spiderants
- Rank 5: Kill 300 Spiderants