Mod of Redemption/Nightshade Core

The Nightshade Core is a Pre-Hardmode. When equipped, it grants 5% increased minion damage, enemies are less likely to target you and grants boosts to all stats at night. However, you are weakened and your life regen is nullified during daytime.

Trivia

 * This accessory, as it suggests, is an accessory essential for nighttime explorations, battles during that timespan and of course, for summoners in a small portion. So, equip it during nighttime to get the most beneficial stats.