Posted 28 August 2013 - 08:40 PM
The challenge started you off at the base of a tree. From this tree, you know what logs are, what planks are, what sticks are, and what dirt is (the block below the log you start off in front of). From that starting point, you can expand your knowledge with a few facts about the blocks in your environment:
Stone: Becomes a different block when dug. The new block can be placed. The new block is smeltable.
Gravel: Falls, occasionally drops something different.
Sand: Falls, smeltable.
Grass: Becomes dirt when dug.
Logs of unknown trees: Craft by themselves into four items, which two of craft into sticks (which are known).
Coal ore: Drops a block-incomparable item, which can smelt items, and is fuel.
Iron ore: Smelts, isn't stone/cobblestone. Smelting product creates turtles.
Gold ore: Smelts, smelting product creates monitors.
Redstone ore: Drops multiple items, crafting with a stick is successful.
Lapis ore: Drops multiple items, crafting with a stick is unsuccessful.
Diamond ore: Drops single block-incomparable item, isn't fuel. Crafts into a pickaxe.
Reeds: Create paper when crafted.
Lava: Liquid checks, and is fuel.
Water: Liquid checks, and isn't fuel.
Anything else either doesn't matter, or... doesn't matter, for the purposes of the challenge.