Note: This may only work in the PC version prior to Beta v1.8. A player can grow mushrooms with bone meal (crushed bones from skeletons), with the brown mushrooms producing raised platforms, and the red mushrooms producing small shelter-like structures. Provided the room is available, and you have killed some skeletons, the brown mushrooms can be used as a flat area for an even base, while the red mushrooms provide shelter from mobs. As the red mushrooms leave some area open, it is vital that the player cover this with another material. Once set up, glass panes or blocks of glass for windows can be added as viewports, and a bed can be placed to sleep in. As a home-building material, it is semi-reliable, but requires some skill and luck to make a home out of mushrooms, as the use of bone meal grows huge mushrooms unevenly, with the mushroom stem growing one or two blocks higher than the lowest possible growth. Huge mushrooms of either type yield more mushrooms of their respective color, with broken blocks yielding up to two mushrooms, and with a possible fifty one blocks for red mushrooms, chances are very high a player will yield more mushrooms than they had grown, making one huge mushroom good starter for more small homes and rooms made with them.
Obsidian is a block that takes fifteen to fifty seconds to gather. It requires fifteen seconds with a diamond pickaxe, and fifty seconds with everything else. If you are aiming to make a near-indestructible building or structure, obsidian is the best choice. Sometimes it is naturally occurring, but often times it must be manually made. First, you will need to find flat lava that is not flowing. Then, collect water with a bucket and put the water onto the lava. Alternately, find flat water and collect lava. A blackish-purplish block should appear. This is obsidian, and requires a long time to collect. It is much easier to just spawn obsidian, but you will need a mod to be able to spawn it in single player mode.
New players love exploring, but when it comes to calling an end to exploration, especially in an abandoned mine, they get lost and end up somewhere completey different, away from home. Besides remembering where you last slept and copying the X, Y and Z values for future editing back to spawn/preferred place, use the following tricks to never get lost:
Explore systematically. If you find a fork in the road, or several forks, take them one at a time. When you reach an end, and mining near it yields nothing, then either mark it or use a common block (like gravel) to seal a path off.
Set breadcrumbs. While mining and exploring, be sure to mine up bits of the floor, using cobblestone or a block unlike the floor as a pointer to the way out; or an ore block to note an intersection, so you have something to identify where you began later. While this will damage your pick more, knowing the way back is more valuable than some tool, especially since the wooden planks in abandoned mines are abundant.
Keep natural landmarks. Scoop up the first source of water that leads to nowhere useful, but leave everything else. Some of the water flowing from walls may prove useful for exploration. Also, if there is lava out of your way, do not go out of your way to put it out -- it emits light, which may be encased in a structure with glass (panes) as natural lighting.
Know the way outside, and know when there is lava. Since beta version 1.8 and the revamped lighting engine, knowing when you are close to ground is easy. Torches emit a bright light that fades into warmer tones. Lava has a brighter radius of light, meaning its brightest point is bigger. If you see light that you did not create, then it is obviously a lava pool. Outside light on the other hand uses cooler tones. When you are close to ground, it does not have the warmth of torch light, taking on a more fluorescent white color near the rock, or at night time, a light shade of blue.
Note: This was done in Minecraft 1.9 Prerelease 3 on the PC version. The added, useless ingredients that have been in version 1.9pre1 and version 1.9pre2 can now be crafted into various kinds of potions for version 1.9pre3, which indicates that this system may remain mostly the same on release. However, all information is subject to change. In order to even make potions, a visit to The Nether is necessary. Certain required ingredients can only be obtained there:
Crafting table Bottles: Made from glass the same way buckets can be made with Iron Ingots: Three pieces of glass, in a "v" shape. Brewing Stand: Made with a solid row of cobblestone, with a Blaze Rod (obtained from defeated Blaze mobs in the nether) in the middle, one row up. Nether Wart: Only obtainable in the Nether, and mainly in Nether Strongholds Water
Potions are multi-step items, requiring various ingredients to produce different effects. While there are three different type of bases, the one that matters at this time is the Awkward Potion, which is made by using a Brewing Stand to brew bottle(s) of water with a Nether Wart. Up to three can be made, so you may as well not waste Nether Wart and make three potion bases, every time. To start making useful potions, you need non-base potion ingredients. Some require even more steps. Below are details of the non-base ingredients, including what they yield when brewed with an Awkward Potion. Also, the Fermented Spider Eye can be combined with other potions to produce negative effect potions.
Made from refined sugar cane. Yields: Potion of Swiftness With Fermented Spider Eye: Potion of Slowness
Must be obtained from a killed (Cave) Spider. Yields: Potion of Poison With Fermented Spider Eye: Potion of Harming
Fermented Spider Eye
Spider Eye, plus sugar and a brown mushroom Yields: Potion of Weakness
Must be obtained in The Nether, from a killed Ghast. Yields: Potion of Healing With Fermented Spider Eye: Potion of Harming
Must be crafted from a Blaze Rod, obtained from a killed Blaze in The Nether Yields: Potion of Strength With Fermented Spider Eye: Potion of Weakness
Kill a slime to get a slime ball, then kill a Blaze in The Nether to get a Blaze Rod. Craft the Blaze Rod into Blaze Rod Dust, then craft the Slimeball with the Blaze Rod Dust. Yields: Potion of Fire Resistance With Fermented Spider Eye: Potion of Slowness (possible placeholder for another potion)
Note: These potions can also be enhanced into Tier II potions by brewing them with Glowstone Dust (obtained from The Nether), and their length of effect can also be enhanced with Redstone Dust (obtained from main world). Also, without making the Awkward Potion, the (currently useless) Thick Potion can be made from Glowstone Dust, and the (currently useless) Mundane Potion from Redstone Dust.