Holds a single byte, where each bit relates to an item or room state as follows:

Bit	Relating To
00	Entering the deep pool of water
01	Entering the bleak moorland
02	Entering the crystal cavern
03	Picking up the acorns
04	Placing the sword on the stone slab
05	Killing the Fomorian tribe
06	Entering the Vale of Rhia
07	N/A

Used mainly as a flag to ensure that points for game milestones aren't awarded more than once.