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|Attack Strength||9px-Half Heart.svg|
|Spawn||After mining block 46 in extreme hills biomes or from spawners in strongholds|
Silverfish can spawn from silverfish blocks and monster spawners . They are also able to spawn, albeit rarely, underground in extreme hill biomes, inside of certain blocks. In the latter case, they can only spawn in light level 11 or lower, except on top of stone blocks, where they can spawn at any light level. They also cannot spawn within a five block distance of any player. These restrictions only apply when spawning from a monster spawner, and not from a Silverfish block.
When attacked, Silverfish may awaken nearby Silverfish blocks. This can lead to a terrifying swarm if there are enough in the vicinity, and in which an uncontrolled swarm can quickly destroy dozens of stone bricks within a Stronghold. They scurry away after the player moves a short distance. They do not have the same sounds as spiders since the 1.0.0 update.
It is advised to avoid conflicts with silverfish altogether, as they will simply generate a massive swarm that can easily out-gun an inexperienced player. If the player does, however, choose to challenge silverfish, it is advised that they wear armor as silverfish can quickly deal massive amounts of damage as the swarm grows. Melee weapons are advised as silverfish are the smallest mob that naturally spawns. If the player is experienced with a bow, then using ranged combat may reduce the size of a swarm.
A simple tactic to combat a swarm of silverfish is to simply build a two-block high pillar and attack from there, as silverfish do not have any range and only deal damage via contact.