LegionCraft is a OneBlock server where you start on your island and grind to grow it bigger.
There are challenging bosses and when you beat them they drop keys. You can use the keys on crates for rare loot and epic gear.
It also has chunk hoppers so you can automate parts of your island. The server says it is no pay to win so it feels more fair while you build grind fight and loot.
OneBlock Boss Hunts on LegionCraft
GG.MINEWIND.NET New Server IPOneBlock Bosses And Key Loot
I found a OneBlock server called LegionCraft and it is all about building up from your own island and grinding to get stronger.
There are challenging bosses and when you beat them they can drop keys. You can use those keys for rare loot and there are crates with epic gear and rewards.
You can also use chunk hoppers to automate parts of your island. The server says it is not pay to win so it feels more fair if you just want to play and grind.GG.MINEWIND.NET New Server IP