So I was thinking for survival a smart and particularly possibly popular idea could be buying a spawner from an admin shop. There would be several things to balance this out though and some spawners would not be allowed to be bought.
First of all for this to work in my eyes only an OP or SOP++ can summon a spawner. (There is a spawner plugin I believe). Spawner types will be limited to members so that they do not have overpowered creeper farms. Only Zombie and Skeleton and other basic non explosive mobs should be available to members. Creeper spawners may cause issues so there will need to be rules for these. One rule could be that it must be a DROP FARM ONLY. No xp. The chances of it exploding are very high if its an xp farm. Creeper spawners could be very useful for potions. Damage may also be needed to be turned off for creepers. Another rule is that the creepers must be in an enclosed area and the walls need to be 3 blocks thick (maybe 2).
So now for the moment which will probably balance it out most. How much will these things cost? Well, the only spawner in the 1000-2000 dollar range should be zombie with skeleton and spider (not cave spider) following at 1800-3500. The most expensive should definitely be creeper spawner. You should earn this one. It should be around 4000 - 5000 dollars. Now these are expensive as all heck but can be negotiated down by staff is this suggestion is reviewed. Then again PCB xp farming could be ruined by spawners going under 1000 bucks a piece. Staff only could spawn these and then sell to player.
Banned Spawner List Ideas ! - ! : Enderman Spawner - already banned anyways. Enderdragon spawner - I don’t have to explain this one… Elder Guardian spawner - Guardians might already be pushing it. GUARIDIAN spawner - really can’t explain this in depth. This one staff would have to decide. Ghast Spawner - Hell no. The perfect tool for a griefer. Shulker spawner - How would this even work? Any and all Golems - No need for a golem spawner. Any boss spawner - For obvious reasons. Zombie pigman farmer - Overpowered as it could in theory give tons of gold for beacons and golden apples.
Anyways please consider this idea!
Thanks for looking!