When a nether portal is broken and replaced in quick succession then pigmen will spawn on mass, producing vast quantities of gold very quickly.
This issue relates to the issue MCPE-97973 and this is where MCPE-97973 originated from.
I have submitted this under the "Private" category as idk whether this classes as a dupe/exploit.
This tends to work best with larger portals (in my tests i used c.20x20) portals. About 2-7 pigmen spawn a second when using observer clocks and trapdoors to break the portal.
Linked issues
is blocked by 1
is duplicated by 4
MCPE-96966
Breaking and re-lighting a nether portal causes pigmen to spawn in the portal faster than usual
Resolved
MCPE-109002
Zombified Piglin Portal Glitch (Instant Death)
Resolved
MCPE-160042
Zombie pigman will spawn sometimes when the portal created
Resolved
MCPE-187906
The constant opening and closing of the Nether portal makes it easier for the Zombified Piglin to spawn.
Resolved
Comments 20
The behavior described here has already been severely nerfed by the portal breaking changes in 1.16.100.55 beta. However, some problems with those changes are raised in MCPE-99650.
I can confirm that it causes lag. It has been nerfed but still works well enough to yield tons of gold over time.
I am removing this report from "Private" security because it does not deal with an exploit (i.e. item duplication, tricking the game engine, or griefing) and does not contain personal information. The behavior reported here is the basis of NavyNexus' gold & xp farm, which was linked in the description of the duplicate report MCPE-96966. Regardless of how one might feel about whether that farm and its output is balanced or good for the game, and regardless of whether the the possibility of a farm like that is intended by the developers, it is at bottom a farm design based on game mechanics.
With regard to the mass spawning of pigmen and the output of NavyNexus' farm design, it is actually on par with Java gold farms that take advantage of natural zombie pigman spawns in the nether. For example, in this video (timestamped) Mumbo Jumbo calculates that his 1.16 gold farm will produce 3200 gold ingots/hr. NavyNexus' farm produces about 3600. If you were to build a farm like Mumbo Jumbo's in Bedrock it would not give anywhere close to the same output due to Bedrock's spawn radius and monster population caps being vastly smaller. Thus, taking a broad view, the portal ticking mechanic in Bedrock provides a kind of parity.
What on earth do you mean “Causing lag”? This cannot be produced accidentally. The fixes to this have made the problem considerably worse. Why wouldn’t you want this? As GoldenHelmet explains, it’s just parity.
This was working in previous versions of the game as well.