"Curse of Clones" : player head , cloned mobs and unique Silverfish feature

When a player found a stronghold , it's easy the idea to break the spawner of silverfish because it is too much close the end portal and there are useless so

The Ideas:

1. if any silverfish like with stone types when it still close at a mob , the silverfish could turn intro a "clone the mob" (the spawn around the silverfish need to allow the hitbox of the other mob and only mobs that can spawn on darkness or "allowed by a tag" , the clone is a new entity that using a nbt tag can be changed the AI and model but have a blue overlay to diversify a original by a clone) with same ability (like creeper can blow up or skeleton can shot arrow) and same model but if killed it doesn't have same loot table, this could be mixed with player head causing that a cloned mob with around a player could clone with same skin , when killed with a charged creeper it will drop a player head with the same skin of the mob 

[this feature could be implemented like as item display entities that allow to emulate a "not physical item" and still similar at illusioner but much more "friendly"]

2.  if the spawner was moved on another room when still full dark , fill a few of mobs with them spawner and mixed with previous idea could be much powerful fight because when silverfish spawn they will convert on other mobs and can create like a horde of mixed mobs that can increase the difficulty of the stronghold much more ; on replace of the old place could be placed a chest with something or the missing stairs