Glitch: Entity Duplication
Entity duplication occurs when you teleport somewhere around 250k pixels into a chunk, that had already been generated before but wasn't already loaded in memory. This type of long distance travel causes the chunk to load twice, once by the player entity and once by the camera entity. This will duplicate all the entities within said chunk, while all the terrain and liquid will simply overlap, negating any duplication effects on their part.
It is possible to cause this type of duplication by using any portal (except Leviathan portals) in a Parallel World sufficiently far away (8 or more PWs), the destination chunk will be duplicated. It is also possible to duplicate any chunk on demand with a sufficiently long range Long Distance Travel wand.
Duplication behaviour to keep in mind:
- All physics objects, items (potions, tablets, etc), wands, spells, enemies, are entities
- Anything that runs Lua is an entity, and can be duplicated
- The Holy Mountain wand cast display eventually causes huge lag inside Holy Mountains
- Trigger zones such as the one in Avarice Diamond will duplicate
- Vines cause rope physics lag, it is not possible to erase them from the world by any means, and they keep resetting their position if they move too far from their anchor point. This will quickly get out of control.
- The portals cause unchecked particle lag, if duplicating Holy Mountains, one should drain the teleportatium to close the portals.
- Chests (including Greater Chests) will keep their RNG seeds, so all of them will contain the same loot.
- Orb of True Knowledge can be duplicated, as they create huge amounts of unchecked particles, one should be wary of freezing their game.
- More about Orb duplication can be read at Advanced Guide: 34 Orb Ending