We have released Spawner keys for the Mining world!
This will help users grind various things such as EcoDollars, EXP, and especially McMMO Levels!
Keep the following in mind:

• Once a Spawner is placed, it cannot be destroyed!
• The Mining world resets every month on the 1st. Any Spawners you placed will be gone during the Mining world reset, however any keys you have in your account will remain, as will any Spawners in your inventory or storage via the Rising world.
• There is no need to place your Spawners. You can always save them, collect them, and auction them via our auction system. Spawners are confirmed working with the /auc system on EcoCityCraft!

Purchase:
https://shop.ecocitycraft.com/category/1075220
Information:
https://ecocitycraft.com/forum/wiki/main-spawner-crates/

This is experimental for the month of April, 2019.
Should there be unforeseen effects to the economy in regards to nether stars, we will simply stop selling them for May's Mining world reset.