Oh i didn't realized that you were able to customize it down to the damage.
If you could,
I need the spiders to have 10 health but will be upgradable, so just put the default health to 10 and make it into a variable
Damage also will be upgradable, so default is 1 damage, they will attack any close mobs or players,
spiders getting summoned... well that's a bit tricky, i have something else that creates the spiders, so maybe summon the spider after 5 seconds if the player right clicks a beacon with 3 gold (that only that player can use once they place it) for now.
Players can summon as many spiders as they want as long as they have 3 gold pieces that is given to a beacon (consumed by the beacon)
Anything else needed please tell me