Ask Hi_iH, his playtime is 100+ hours on Hollow Knight XD

Later you get a upgrade to dash which lets you pass through those

Like really late into the game

rn you should go to the city of tears

u mean the super dash?

also wtf is the city of tears

i found the mantis thing

the 3 bosses

You need the crystal heart which requires you defeating  hornet in greenpath and the Mantis lords to get mothwing cloak and mantis claws

If you beat the mantis lords go to crystal peaks and progress until you find it