We already know that in Minecraft 1.16, an end portal can generate with 12 eyes of ender already placed, such as in the seed -4530634556500121041. The odds of this are calculable: 0.1^12 = 1 / 1 trillion.
Recently the seed 2483313382402348964 which generates the following end portal was discovered:
For all practical purposes this is a complete portal, since it gives immediate access to the end. Then the actual odds of a "complete" portal are higher than 1 / 1 trillion. Do we have an estimate or actual value for the odds of a complete portal, including this case?
I've noticed that the completed part of the portal is in a different chunk than the rest of the portal, which is probably a hint as to why the generation happened like this.
Best Answer
This is what I believe based on 1.16.4 MCP Reborn decompiled code.
The end portal will only generate if all eyes are placed in which sets
flag
. And if 1.16 is like previous versions, the RNG is seeded per chunk, so a portal can cover 4 chunks, but the chunk with the glitched portal still requires 12 eyes to spawn chance. Source: zolsticezolstice (moderator of r/MinecraftSpeedrun)So the chance is still on the order of 1/1 trillion rather than 1/6400, but increased due to portals generating over multiple chunks.
From
StrongholdPieces.java
:My guess is
p_230383_4_
is theRandom
object that does the RNG which comes fromgenerateFeatures
inBiome.java
, which comes fromSharedSeedRandom
, which is seeded per chunk.For the sake of having some numbers, let's assume the portal generating per chunk assumption is correct, and also the portal center is chosen uniformly within a 16x16 chunk. Then if the portal center is on one edge of the chunk, end portals are calculated over two chunks, and if the portal center is in a corner of a chunk, end portals are calculated over 4 chunks. So the two chunk case has 4*14=56 possible positions and the chance of at least one chunk having a 12-eye RNG is 1-(1-10^-12)^2 ≈ 2*10^12, and the four chunk case has 4 possible positions with chance 1-(1-10^-12)^4 ≈ 4*10^-12. The total chance is now about (196 + 2*56 + 4*4)/256 * 10^-12 ≈ 1.266 * 10^-12, so about 25% more likely as the original 1 / 1 trillion chance, but still on the same order of magnitude of nearly impossible.