The server now has blue axolotls!

As you may know, once one exists, it isn't hard to get more through breeding. So now anyone who wants one can have one.

Continue reading if you'd like to learn how the first blue axolotl came to exist.

It started with MewTwoIsSussy telling me about how he wanted a blue axolotl. I had read on the Minecraft wiki a week earlier that axolotls spawn in lush caves in water that is above clay blocks. So I thought it would be easy to just find a cave and put some water of clay blocks and wait for one to spawn.

So we set out to find a lush cave. We started just mining underground, which yielded nothing. Then MewTwoIsSussy read on the Wiki that we needed to find a particular tree, and under it would be a lush cave. So we flew around for a while looking for the tree, and through a miracle of Minecraft being a poorly-programmed game with lots of flaws, my chunks quit loading, which allowed me to spot something underground in the distance: Dripleaves. So I flew over to them, dug into the ocean floor, and found a lush cave. This was five days ago according to this screenshot I accidentally took.

We started by looking around, but while there were axolotls, there were no blue ones to be found.

So to put my plan into motion, we constructed this now-empty pool, filled it with water, and sure enough, axolotls would spawn in it. Also some tropical fish would spawn.

MewTwoIsSussy tried breeding a few axolotl, but obtained no blue babies. I made a separate tank without a clay bottom to allow tropical fish to spawn in. I then read on the wiki that the chances of getting a blue axolotl were 1 in 1200. Since our efforts were producing very few, we gave up for the day.

The next day I returned to try to do better.

One problem was that there is a server-wide spawn cap of 5 for axolotl. So if axolotl were anywhere else on the server, they wouldn't spawn in my pool. So I went all throughout the cave and removed any other water, so that the only suitable spawning location was in my pool.

Another problem was that nothing in Minecraft spawns within 24 blocks of a player, and so it was necessary to leave the pool area to allow axolotl to spawn. Wanting to not have to waste time walking back and forth, I removed the water from the pool and constructed a new spawn location.

Originally it didn't look as it does in that screenshot. The first was more narrow, didn't have fence gates, and went upward at a lower slope. The idea was to allow the axolotl to spawn 24 blocks away, then push them down to me. However, there was one problem: Axolotl aren't affected by flowing water.

So the first modification I made was to make the drops 2 blocks high, so that as the axolotl swam around, once they fell down, they couldn't swim back up. So they would slowly make their way towards me, at the rate of maybe one a minute. To speed that up, I increased the slope as well, adding fence gates to block the flowing water after only 4 blocks instead of 7.

However, even that wasn't doing a lot to bring the axolotl to me. I would often have to go up to them with a bucket of fish so they would follow me back to dry land where they were slow enough that I could reliably catch them in a bucket of water. So I eventually removed the water from the upper half of the spawning area and settled for walking away from the remaining flowing water to put me out of the 24-block range of the water so that they would spawn closer to the catching area.

I then spent a day collecting axolotl in buckets and storing them in chests, waiting for a blue one to spawn. Then CaptainKirk55 came to see what I was doing and informed me that blue axolotl don't spawn naturally, they can only result from breeding. I checked the wiki and, sure enough, though it was only listed in an update note, the information was there. So my whole day of effort had been for nothing.

After wondering what to do for a while, I came up with a new plan: I would breed the spawned axolotl, then kill them, allowing more axolotl to spawn. This would avoid having to wait for the 5 minute breeding cooldown by giving me new axolotl to breed just a minute later.

This meant that I needed a lot of tropical fish. I used the first fish spawning pool for a while, but it too was too close by, so I created a new one. It is shown below, though it now has no water in it.

This was built 32 blocks away from where I was breeding the axolotl, and so every time I returned to it, it was full of tropical fish. However, it was still a big waste of time to have to go to it and collect them, and then return with them to breed the axolotl. So, while I got a new pair of axolotl to breed about once a minute, I was probably only breeding a pair once every two minutes because of the time needed to collect fish. At this rate it would take about 20 hours to obtain a blue axolotl, so I needed a better way to get fish and a better way to spawn axolotl.

So I had a new idea: I would create an area to spawn axolotl that was 24 blocks above the breeding area, and allow the axolotl swim over the edge and drop down to me.

This was also about the time that CaptainKirk55 and GreenFlem began helping me.

I started by constructing a new spawning area, shown here in it's final form, but the original was only one layer.

The axolotl spawn in this clay and water area above that room, and simply drop over the edge eventually and land in the breeding room.

At first the axolotl would drop onto waterlogged slabs, but the babies were still submerged enough that the water made the white ones look blue, making me fearful that, if a blue one was born, I wouldn't notice it and kill it along with the non-blue ones. So I then redesigned it so that they fall onto a thin layer of water, but then they would swim around in it a lot, making them hard to target with a bucket of tropical fish or an axe. So then I made the area for them to drop down into.

This was faster at spawning and bringing axolotl to me, but now we needed to solve the fish problem.

My first thought was to use bubble columns to push the fish up into flowing water which would push them to the breeding area, but fish aren't affected by flowing water. In fact they often seem to swim against it. So then we built a new fish spawning pool, again 24 blocks above the breeding area, but again, getting the fish to leave the pool of water that they were in and fall down to the breeding area was a challenge.

It took about a day for us to get to it, but what eventually worked best was this design which uses dispensers with water buckets to create water for the fish to spawn in, then removes the water so that they fall down.

We also over time came up with some ideas to be more productive. At first I decided to not kill the babies. Since they weren't in water, they would eventually die anyway, and they couldn't be confused with the breeding adults and didn't count against the spawn cap. Then CaptainKirk55 came up with the idea to keep the babies, since they would eventually grow up and then they could be bred and killed too.

So under the breeding room I constructed this redstone stuff which controls dispensers with water buckets under the slabs that are at the bottom of the breeding area, and occasionally put out some water for a second just to reset the 5-minute death timer that begins when axolotl are out of water.

This allowed the babies to remain alive and because each two babies, when grown, can produce another baby, that's 50% more breeding opportunities. However, it gets better, because those babies can grow and produce more babies, adding another 25%, and their babies add another 12.5%, and when you add it all up, keeping the babies until they can be breed increases the breeding opportunities by 100%.

The babies were in the way though, so we built a new room for the babies.

In this room the baby axolotls were kept until they became adults, then bred and killed like the naturally-spawned ones, so as to avoid the problem of knowing which adults could be bred and which could not.

Then GreenFlem came up with the idea of immediately bucketing the naturally-spawned axolotl, so that they no longer counted towards the spawn cap. So I began doing that and moving them to the baby room where Kirk and GreenFlem would breed them and kill them.

At this point I timed how many spawns we got in five minutes to estimate how long it would take to spawn 1200 babies at our now much-faster rate. We got 51 spawns in five minutes. Since that would result in 25 babies, and those babies would eventually result in 12.5 babies, and those in 6.25 babies, for an eventual total of 50 babies per five minutes, we would only need two hours to produce 1200 babies.

That's quite an improvement. It started with MewTwoIsSussy and I spawning them in a pool in a process that might have taken 80 hours, and ended with a highly-optimized process that could spawn one in only 2 hours with 3 people working on it.

As it turns out, it was only about 45 minutes after this final optimized process was put into play before CaptainKirk55 bred the first blue axolotl on the server.

We immediately fed it about 50 tropical fish to turn it into an adult.

We then bred it with a white axolotl, and got a second baby blue axolotl. We also fed it about 50 tropical fish so that we had two adults, and with two blue axolotl, breeding has a 100% chance of resulting in another blue axolotl.

So now we have so many that they can't be contained. Despite it being too high for them to climb out, through collision effects they're escaping the spawn room anyway and going after the tropical fish.

So, do you want a blue axolotl? They're so easy to produce now that there's no point in selling them, so we'll be giving them away for free to anyone who wants one.

If you would like to see this historic site for yourself, or just get some free axolotls, you can visit the site via the teleporter named "Blue Axolotl Breeding Site."