How to get into Humbeldeless World - 

Now in Overworld you can meet strange structure - Lushy Castle

There can be found Terraquartz Altar -

Terraquartz Altar - suspicious block, that can convert humbledless materials to new useful equipments for player 
When you found structure and altar, just try to click on block with enderite nugget and green glass - to get Humbledless Spark

Finally - click with Humbledless Spark on portal-frame-like construction in some of structure's rooms

Recipes on Terraquartz Altar:
Item in left hand + Item in right hand: Result
Enderite Nugget + Green Stained Glass = Humbledless Spark

Humbledless Spark + Stick = Enderite Blockcaster

Enderite Nugget + Enderite Nugget = Enderite Ingot

Terraquartz Bricks + Golden Nugget = Chiseled Terraquartz Bricks

Advanced Recipes:

Enderite Blockcaster + Terraquartz Essence + Starlight Glint = Starlight Blockcaster

Starlight Blockcaster + Radiant Membrane + Guardian Pulp = Radiant Blockcaster

Arrow + Enderite Ingot + Mossy Terragold = Soul Stealer Arrow

Bow + Enderite Ingot + Mossy Terragold = Soul Stealer Bow
Terraquartz Leaves Propagule + Enderite Ingot + Mossy Terragold = Terraquartz Branch

Upgrade, click on Terraquartz Altar with Starlight Blockcaster, then:

Radiant Blockcaster click on altar with Mossy terragold, Haphararoom Fungus and Guardian Pulp in inventory