A spider jockey is the rare, but deadly combination of a spider and a skeleton, with both their strengths and weaknesses.
Killing the spider will cause it to drop 0-2 strings, 0-1 spider eye and 5 experience points. Killing the skeleton will cause it to drop 0-2 bones, 0-2 arrows, 5 experience points and there’s a chance it drops a bow, which could be enchanted with Power I, though this is extra rare.
Note that the spider eye and bow can only be dropped if they mob is killed by the player.
A spider jockey only spawnws in the Overworld and are created when a spider spawns. Spiders have a 1% chance of spawning as a spider jockey.
Despite being a combination of 2 mobs, they don’t work together very well. The spider is in control of their movements, but only considers itself when walking around. This means the skeleton can die very quickly, which makes them that much more uncommon. When the spiders walks around, the skeleton can easily get stuck in other blocks, which will suffocate him. The skeleton will also burn when it comes in contact with sunlight, though the spider remains unaffected and keeps wandering around.
Killing either one of them will not kill the other, which will live on as a normal version of its kind. This is important to know when engaging a spider jockey. The skeleton has the highest attack strength, though going after the skeleton is only advised if you have a bow. Using a sword is very difficult as the spider will simply push you away.
Engaging the spider first leaves you open to the skeleton’s strong attack. To overcome this you could simply create a blockade. If you leave an opening of 2×1, the spider will fit through it while the skeleton will be suffocated.
Alternatively, by digging a 2 block deep hole and hiding in it, the spider will usually walk on top of you. You will be able to safely attack the spider and the skeleton will shoot the spider while trying to hit you. Though the spider doesn’t always walk over the hole, it might simply wait in an ambush.
Wolves are a great way to kill a spider jockey, though it’s important to know the wolves will attack whatever attack you first or whatever you attack first. Sending them after the spider is highly advised as the skeleton is usually out of range. Once your wolves are busy with the spider, you can deal with the skeleton. If you use enough wolves they’ll keep pushing the spider, which makes sure it can’t get to you. However, the spider will usually shift it’s focus from you to either one of the wolves, so this isn’t a major issue. Note that using just 1 wolf will usually lead to its death, though it does buy you some time to either run or attack.