This is the fifth trap like this that I've made and the only one that hasn't worked so I'm really frustrated and out of ideas. It's the classic box with water channel design, the mobs walk into the water and drop 20 blocks so I only need 1 or 2 hits with a wooden sword to finish them off. I have:
lit up all surrounding areas and caves within a 140 block radius
ensured the trap is completely dark on the inside
switched to peaceful to clear out all mobs before switching back to normal
increased the fall to 22 blocks (at my afk position I am 28 blocks away from the area where mobs are supposed to spawn
I've used this design in single player and multiplayer alike and it's always worked before. The only differences are:
Y=90 instead of in the 50-60 range where I've built them before (Biome: extreme hills. I don't see why this would make a difference over prairie and savannah but)
I gave the mobs a 2 block high space to spawn instead of my usual 3 blocks to save on resources. (A few tutorials on Youtube suggest this to keep Endermen away and have had no issue)
The only thing that seems to work is walking around in the ~15 block radius around the base of the trap, but even then the most that it's ever spawned is 4 zombies. Day or night makes no difference, zombies are the only things that seem to want to spawn, the only other mob was a creeper.
Check your render distance. 10 or more and you should have normal rates, provided you've gotten all the lighting work out of the way.
Is this on a server? Just give up and go hunting. Mobs will spawn in all the chunks that players are in, so more players means more mobs that aren't going to spawn anywhere near you. Also, unlike in single player, the clientside render distance isn't used for mobspawning purposes; instead, the server's render distance is used so if the server has it set really low then mobspawning is just going to suck.
What do you see on your entity count in the F3 screen when you have the trap in your field of view? If your entity count is going up but mobs just aren't seeming to drop, either you're getting bunches of spiders hanging out on the walls or somehow mobs are seeing the fall as a fall and actively avoiding it.
Also, what version are you using? I think there may have been some AI changes in the 1.9 snapshots to make mobs smarter about trick falls, so something from earlier versions that worked just fine in 1.8 or earlier might no longer work at all/as effectively.
This is in a single player world and I'm running 1.8.9.
It's almost 2am and if I open Minecraft right now I'll never get to bed lol, so I'll have to get back to you with the render distance and entity count tomorrow after work.
This is the fifth trap like this that I've made and the only one that hasn't worked so I'm really frustrated and out of ideas. It's the classic box with water channel design, the mobs walk into the water and drop 20 blocks so I only need 1 or 2 hits with a wooden sword to finish them off. I have:
lit up all surrounding areas and caves within a 140 block radius
ensured the trap is completely dark on the inside
switched to peaceful to clear out all mobs before switching back to normal
increased the fall to 22 blocks (at my afk position I am 28 blocks away from the area where mobs are supposed to spawn
I've used this design in single player and multiplayer alike and it's always worked before. The only differences are:
Y=90 instead of in the 50-60 range where I've built them before (Biome: extreme hills. I don't see why this would make a difference over prairie and savannah but)
I gave the mobs a 2 block high space to spawn instead of my usual 3 blocks to save on resources. (A few tutorials on Youtube suggest this to keep Endermen away and have had no issue)
The only thing that seems to work is walking around in the ~15 block radius around the base of the trap, but even then the most that it's ever spawned is 4 zombies. Day or night makes no difference, zombies are the only things that seem to want to spawn, the only other mob was a creeper.
I don't really think these traps work too well any more. Mobs become idle if you're not close enough (32 block radius). So once they spawn they may have a few seconds of movement in them, but once that idle hits they just sit still until they despawn. So if they don't get into the channel in that initial movement they just hog the mob cap and block spawning space, reducing your efficiency
So when you're standing your 28 blocks away, the only mobs which ever have a chance to even move beyong their initial burst of movement when they spawn are the ones which are in the very closest part of the trap to where you are standing. That's why when you walk around the base 15 blocks away you start to see some fall, because you're back in range of them and enabling them to move.
If you're not seeing spawns at all I can see two reasons behind that too. One, you may not have actually lit up as many caves as you thought. There's lots of cave systems which are can be pretty much right next to each other but not actually connect, or cave pockets which connect to nothing at all. The only real way to be sure you got them all is going into gamemode 3 and going into the wall to see through the ground, or some other sort of see through blocks glitch.
The second reason is that by the pictures it doesn't actually seem like you have a ton of spawning space inside of there. It looks like maybe 1-2 floors? I can't really see by the pictures provided but it doesn't seem very big.
Need a good universal mob farm? Check out the Double Shift Towers. Designed for 1.9 and gets 22,000 Items / Hour with a very simple redstone set up - https://www.youtube.com/watch?v=jL8aoJpjjgU
Yeah I agree with Vonderbach, I am in love with how you designed that. I know this is off topic but if you have any other unique designs you'd care to share, I'd love to see em !
This is the fifth trap like this that I've made and the only one that hasn't worked so I'm really frustrated and out of ideas. It's the classic box with water channel design, the mobs walk into the water and drop 20 blocks so I only need 1 or 2 hits with a wooden sword to finish them off. I have:
I've used this design in single player and multiplayer alike and it's always worked before. The only differences are:
The only thing that seems to work is walking around in the ~15 block radius around the base of the trap, but even then the most that it's ever spawned is 4 zombies. Day or night makes no difference, zombies are the only things that seem to want to spawn, the only other mob was a creeper.
Check your render distance. 10 or more and you should have normal rates, provided you've gotten all the lighting work out of the way.
Is this on a server? Just give up and go hunting. Mobs will spawn in all the chunks that players are in, so more players means more mobs that aren't going to spawn anywhere near you. Also, unlike in single player, the clientside render distance isn't used for mobspawning purposes; instead, the server's render distance is used so if the server has it set really low then mobspawning is just going to suck.
What do you see on your entity count in the F3 screen when you have the trap in your field of view? If your entity count is going up but mobs just aren't seeming to drop, either you're getting bunches of spiders hanging out on the walls or somehow mobs are seeing the fall as a fall and actively avoiding it.
Also, what version are you using? I think there may have been some AI changes in the 1.9 snapshots to make mobs smarter about trick falls, so something from earlier versions that worked just fine in 1.8 or earlier might no longer work at all/as effectively.
This is in a single player world and I'm running 1.8.9.
It's almost 2am and if I open Minecraft right now I'll never get to bed lol, so I'll have to get back to you with the render distance and entity count tomorrow after work.
I don't really think these traps work too well any more. Mobs become idle if you're not close enough (32 block radius). So once they spawn they may have a few seconds of movement in them, but once that idle hits they just sit still until they despawn. So if they don't get into the channel in that initial movement they just hog the mob cap and block spawning space, reducing your efficiency
So when you're standing your 28 blocks away, the only mobs which ever have a chance to even move beyong their initial burst of movement when they spawn are the ones which are in the very closest part of the trap to where you are standing. That's why when you walk around the base 15 blocks away you start to see some fall, because you're back in range of them and enabling them to move.
If you're not seeing spawns at all I can see two reasons behind that too. One, you may not have actually lit up as many caves as you thought. There's lots of cave systems which are can be pretty much right next to each other but not actually connect, or cave pockets which connect to nothing at all. The only real way to be sure you got them all is going into gamemode 3 and going into the wall to see through the ground, or some other sort of see through blocks glitch.
The second reason is that by the pictures it doesn't actually seem like you have a ton of spawning space inside of there. It looks like maybe 1-2 floors? I can't really see by the pictures provided but it doesn't seem very big.
Bored enough to watch some vanilla lets plays? http://www.youtube.com/user/Crump3txxix
Need a good universal mob farm? Check out the Double Shift Towers. Designed for 1.9 and gets 22,000 Items / Hour with a very simple redstone set up - https://www.youtube.com/watch?v=jL8aoJpjjgU
You're not being helpful.
by c0yote
I tried it with terrible results. I gave my wife my glasses for a second, a creeper showed up and now my wife is pregnant.
Stupid 3D..
I believe ideally you are with in 24 to 32 meters. Going by what the wiki has.

http://minecraft.gamepedia.com/Spawn
I just want to say that your design is amazing. I love the wooden support members cradling the main hub.
Yeah I agree with Vonderbach, I am in love with how you designed that. I know this is off topic but if you have any other unique designs you'd care to share, I'd love to see em !