Check all corridors for past-self signs.

You study the walls and floor. Brushing against the walls, you manage to find the remnants of a sign. According to this, if you go left you'll find a "lib ar". If you go down, you'll find "du g  n". If you go right, you'll find "slee  n  qu".

Go left if no signs.

Although the vague hints as to what you'll find is somewhat useful, you don't really know which way is best to go. So you go left. The stairs aren't terribly steep, but it's a long climb. Whoever built this castle must have wanted to torture visitors. The rock walls continue all the way up, your flaming spear lighting up the way.

After a long while, and stopping to rest a few times, you reach the top. As you open the door at the top (having carefully checked for any traps and finding none), you find a lot of books. Now this is useful! You pick up a book and read. It's about chemistry.

You have learned a variety of chemical recipes, but the only relevant one is that if you mix iodine and ammonia, you'll get nitrogen triiodide, which is apparently a very unstable contact explosive, but it's not very dangerous. According to the book, it will explode very easily, but very weakly, leaving a purple stain.

/help nicotin withdrawal

Nicotine withdrawal

When addicted to nicotine, going without it for too long leads to withdrawal. You can wait it out and lose the addiction, or you can have a smoke to avoid the stat reduction that comes with the withdrawal.

Up up down down left right left right B A start

You try to mime the Konami code. As you finish, a stone falls out of the ceiling in front of you, almost crushing your skull.

roll a cigarette and smoke only half

You roll a cigarette like you rolled joints back in college. You do it in ten seconds flat. What a glorious cigarette! You light up and puff a bit. As there's nothing noteworthy to do in the library, you figure you'll read the other books retroactively, and head back down.

the other half throw up the stairs to the right,

Given the length of the stairs to the left, you don't think throwing a cigarette up there will give any answers. However, it is a good idea to mark where you've been.

When you've smoked about half of the cigarette, you leave it on the lowest step of the stairs to the left. That way, any future version of yourself will know it's safe.

if no obvious trap to be had listen closely

You listen closely. It's pretty silent.

also,judging by the masonry scavenge about to see if there are any tools or left books inside--

You don't see any tools in the vicinity, and you think the admins will be angry if you try to fit the whole library in your backpack.

You are wearing blue jeans, a white t-shirt, sturdy shoes, and simple boar hide torso protection with pockets taken from the jacket. On your back is the backpack you found with you when you woke up. Your current weapon is a primitive spear. You are not tired. You are not hungry. You are not thirsty. You have (1) unspent skill point(s).

What do you do?