Wear a full suit of Iron armour.

Cook and eat a pork chop.

Use a saddle to ride a pig, then have the pig get hurt from fall damage while riding it.

Use planks and sticks to make a hoe.

Breed two cows with wheat.

Tame a Horse.

Stop starvation using Rotten Flesh.

Construct a furnace out of eight cobblestone blocks.

Smelt wood trunks using charcoal to make more charcoal.

Construct an Enchantment Table.

Place a fully explored Map into an Item Frame.

Discover 100 Locations