Nice, looks freaking awesome. I just wish that Mojang would add rails that could go sideways and upside down. Rollercoasters would become so much better:D
What the first way said, mobs cannot spawn on water. But you can do something like where you flip a button and then water will flow and wash the mobs into a "collecting" area for you to kill easily where they can't reach you.
And make sure that the caves around you are lit well. If there are dark caves around you, mobs will spawn in there instead of the mob spawner!
Also, to make just creepers spawn is not really possible. You can restrict spiders from spawning by making the "spawn pads" not big enough for a spider to spawn, and you can restrict endermen by just making the ceiling 2 high to where endermen can't spawn. But if you have a regular 2 high ceiling, creeper, zombies, and skeletons will all spawn. There is not really a method (yet) to prevent one of them from spawning.
A really good youtuber called monkeyfarm make a very, very, very, very nice guide on the mob spawning behaviors. And an even better mod spawing video.
I have killed blazes with no armor on hard. They are not that hard to kill. What you basically need to know of is their flame attacks. When you heard or see it being shot, move out of the way, or hide around a corner. The hiding around a corner trick is the best imo. This way you come out when the blaze is not attacking and hide when it is. Once you have like 2 rods, go back home and make some fire resistance potions. Then come back and fight the blazes with ease:)
But yeah, you can bring armor and a decent weapon to kill it. Some nice enchantments would be fire protection. But of course that stuff isn't required, it helps.
once you're bored in SSP vanilla, the next thing is to try big modpacks like Tekkit or FTB. Modpacks imo are generally easier to install rather than finding each mod separately. And if you can manage to get bored of that, multiplayer is always a good thing. There are many plugins on server that enhance the game experience.
There really is not a way to avoid caves. There will be caves mostly everwhere you dig. The best way to avoid falling into a deep ravine is to dig 2 blocks down at the same time and stand in the middle of them. If one of the blocks you are digging under has a cave, you will not fall down.
But tbh, if you're making an underground base, then having caves just speeds up the process because then you don't have to mine as much. If you want a world with on caves at all, then a superflat world is the way to go. But other than that, there is no way to avoid caves unless you do something like x-ray and search for a place without caves.
You don't need water for most crops. But if there is water near, then the crops grow much faster. However, there is a way to move water around. Once you get yourself a silk touch pickaxe, you can break ice and move water around
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And make sure that the caves around you are lit well. If there are dark caves around you, mobs will spawn in there instead of the mob spawner!
Also, to make just creepers spawn is not really possible. You can restrict spiders from spawning by making the "spawn pads" not big enough for a spider to spawn, and you can restrict endermen by just making the ceiling 2 high to where endermen can't spawn. But if you have a regular 2 high ceiling, creeper, zombies, and skeletons will all spawn. There is not really a method (yet) to prevent one of them from spawning.
A really good youtuber called monkeyfarm make a very, very, very, very nice guide on the mob spawning behaviors. And an even better mod spawing video.
Link to the mob spawning behaviors:
Link to the amazing mob spawner, that even I use!
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EDIT: I just found this, it should help with posting screenshots:D
http://i.imgur.com/kZr45.jpg
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But yeah, you can bring armor and a decent weapon to kill it. Some nice enchantments would be fire protection. But of course that stuff isn't required, it helps.
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But tbh, if you're making an underground base, then having caves just speeds up the process because then you don't have to mine as much. If you want a world with on caves at all, then a superflat world is the way to go. But other than that, there is no way to avoid caves unless you do something like x-ray and search for a place without caves.
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