Honey

Honey sits at the bottom of Bee Hives and in patches through the Underground Jungle around them, and breaking Hive blocks sometimes leaves a little more behind. In practice you are not hunting it as a material. You are after the regeneration it grants while you stand in it, which is strong enough to design a boss arena around.

Standing or swimming in honey applies a life regeneration effect that lasts as long as you stay and for another 30 seconds after you leave. It adds one health per second on top of your normal regeneration, triples the speed at which natural regeneration ramps up to full, and takes two health per second off damage over time debuffs such as Acid Venom.

You do not need to be submerged, but the pool has to be at least two tiles wide and a bit over half a tile deep. Anything thinner does nothing at all, which is the usual reason a hand poured puddle refuses to trigger it. Pour a full bucket into a two tile trench rather than spreading it.

The 30 second carryover is what makes honey practical during a fight. You never have to fight standing in it. You dip and leave, and as long as you touch a pool every half minute the buff never drops. A few small pools spaced along an arena floor cover a whole boss fight on their own.

• Ring a pool with bubbles and you can run straight through it at full speed. Bubbles stop liquid but pass entities, so the honey stays put while you do not.
• Stacked with heart lanterns and campfires, the total regeneration gets high enough that a band of regeneration stops earning its accessory slot.
• The Lava Shark mount from superheated blood keeps the buff running while moving properly, which is otherwise the trade you are making.
• Flipper potions cut the movement penalty if the fight forces you to stay in the honey instead of beside it.

Honey is the slowest liquid in the game and it slows nearly everything inside it, projectiles included. The Old One's Army enemies are the exception and ignore it. You can drown in honey exactly as you can in water, and every item that lets you breathe, swim or walk on water does the same job here.

That slowdown has offensive uses. Traps like boulders travel slowly enough through honey to land repeated hits instead of wasting most of them on invincibility frames. Visibility is the cost: honey is far murkier than water and extra torches barely help.

Honey does not evaporate in the Underworld, which is the one thing water cannot manage down there. Combined with any of the standard duplication setups, that gives you a way to flood stretches of hell and turn the lava problem into a slow walk instead of a bridge building project. The obvious use is the bottom of a hellevator: a honey pool cancels the fall, cannot burn you, and heals you while you get your bearings.

For sources, a bottomless honey bucket settles it permanently, while honey bombs and honey rockets place it in a hurry. The honey absorbant sponge and dry bombs take it back out. Rain leaves honey alone, so an outdoor pool will not quietly turn into honey blocks on you.