Red Riding Leggings

Red Riding armor is not crafted. The Tavernkeep sells all three pieces for Defender Medals once Golem is dead, so the price is measured in Old One's Army waves rather than ore. Anyone who already ran the event for Huntress armor is buying the same kit rebuilt for late Hardmode, and nothing about the way you play has to change.

The headline is what happens to Explosive Trap sentries. On their own they are one of the weaker Old One's Army options, stuck to the floor and slow to reset. Under the full set they fire quickly enough to out-damage every other sentry of their tier, and each hit coats the target in Oiled, so anything already burning takes extra on top. Plant a cluster where enemies have to walk, or directly below you if you are hovering, and the opening waves of a moon event mostly handle themselves.

The set pushes ranged and summon output at the same time, which is unusual this deep into a world. A pure ranger gets more from Shroomite, and a pure summoner gets more from Stardust because of the extra minion slots. What this set does is let one loadout do both jobs properly. Run it with the Necromantic Scroll, the Papyrus Scarab and a Bewitching Table and a full bench of boosted Xeno Staff minions keeps working while you shoot.

Neither this set nor Shroomite gives a ranger a bonus worth protecting, so the usual compromise is a Shroomite headpiece worn over the Red Riding Dress and Leggings. Even in that build the dress beats the Shroomite Breastplate for ranged output. The leggings are the piece worth arguing over: they carry more summon damage than the Stardust Leggings but no minion slots, so a committed summoner takes the Stardust and a mixed build takes these.

Once you are carrying the Stardust Dragon Staff, or the Stardust Cell Staff instead, the summon half of the set starts carrying more of your damage than the ranged half, and the whole package can pass Shroomite outright. There is no direct upgrade after it, so it usually stays equipped until the Luminite armors come online.