Squire's Great Helm

Squire armor is bought, not crafted. The Tavernkeep takes Defender Medals for the pieces and opens the stock once any mechanical boss is dead. Medals come out of the Old One's Army, so the practical route is to clear waves of that event at whatever tier you can handle and spend the proceeds here.

This is the frontline half of the tavern gear. Melee damage and crit sit next to summon damage, so a sword and a sentry line reinforce each other instead of competing, and the passive regeneration lets you stand through chip damage. It is the alternative to Spider armor for the mechanical bosses and Plantera: fewer minions trailing behind you, more firepower bolted to the floor.

The set is built around one sentry. Ballista bolts fly faster and punch through more targets while you wear it, and taking a hit opens a short window where every ballista you have planted fires far more often. That inverts the usual advice: a player who never gets touched never sees the bonus at all. Plant the posts, fight inside their firing lines, and treat the hits you do take as fuel.

Even outside a summoner build the great helm is worth a chest slot. Swapping it on while potion sickness is ticking gives you a steady trickle of health back for nothing more than whatever headgear you took off, which can cover the gap between healing potions. Valhalla Knight armor is the direct upgrade later, from the same vendor at a higher event tier.