When crafting cake you lose the buckets.
only 10% of the generated games will have slime Mob type.
clay is similar to slime exact percentage is known only to the Mojang team
on occassion when you save underground. when you reload you're on the surface.
if you create a second portal the second portal will return you to the first portals spawn in the nether
if you create a portal in the nether (or more) that portal links to another existing portal, rather than create a counter part in the other overworld
on occassion if you save in the nether when you reload the nether appears to be flat devoid of all terrain execept that impenetrable type of cobble, rendering you stuck.
70% of illumination is needed to prevent monsters spawning in your home, however monsters ignore this rule on occassion.