Grind to git gud for the new bosses that want to constantly tear open your tender and nubile star fish.
what
i didn't grind at all you just explore the caves and look for goods, mine the hardmode ore on your way to wherever you're going
i never grind in this game, it just takes one good weapon or ammunition to get the ball rolling
just look around in the hallow for hallowed mimics, get destroyed because they body slam through the walls, go make a light key and then fight one on the surface
repeat until stormbow, then get like 300 holy arrows (which is 300 arrows, 3 unicorn horns and 9 pixie dust) and just destroy literally every boss
also get wings