Puzzle Dungeon: Floor 2

Question

After bravely circumventing floor one of Puzzlandia's dungeon and descending the staircase, you find yourself in room $2^4$, or $16$ (as the staircase said.)

Items you have:

rusty sword (+1 combat power, 1 Hand)

Good luck!

Room 11

As soon as you enter this room, jets of fire shoot at you! You manage to escape and make it back into room $(6-2)(2^4-3*4)$.

Room 12

You finally get past that door in room 16, and find yourself in... an identical room? You hope the doors take you different places.

There is a door here that takes you back to room 16.

There is a trapdoor here that takes you to room ykculnu.

There is a door here that takes you to room self-description.

There is a passageway to room neuf times dos.

Room 13

Really, you should have known better than to enter an unlucky room.

But you did, anyway.

A swarm of black cats jump on you, swarming you until you die. GAME OVER.

Room 14

There is a strange twenty-sided die here. You pick it up, and your combat power is permanently increased by $1$!

You found a doorway back to room 16.

Room 15

When you enter this room, words appear on the walls.

beijqsiyojarwlm

Shadows start swirling around you until they take the shape of a giant shadowy hound! You need a Combat Power of $6$ or higher to kill the hound. If you can't, it's GAME OVER. If you kill the hound, read what's under 'excited raichu is a nerd #3'.

Room 16 (Start Here!)

There is a staircase leading up to room 7 here.

There is a trapdoor leading to room netter thewy here.

There is a door leading to room 13102213301233 here.

There is a passageway leading to room beiibyafxfdezqhime here.

Room 17

There is a llorcsafoflah here.

There is a passageway to room the next room here.

Room 18

There is an altar in this room. If you have the two halves of the scroll, you can combine them here.

Otherwise, you can return to room 12.

Room 19

There is a button labeled Pointless Button #2 here.

There is also a passageway back to room 23.

Room 20

There is a nretnalcigam here.

There is a passageway to room onusonemecrotac here.

There is also a passageway to room once here.

Room 21

As soon as you enter this room, the door slams shut, and green lights in the shape of letters appear on the walls.

MEMES AREN'T FUNNY

Then a laser zaps you to death. GAME OVER.

Room 22

There is a pxlwwfipciwlt here.

There is a passageway to room thgienet here.

Room 23

There is a sleeping dragon here. You need a total Combat Power of $3$ or higher to kill him, but you can just sneak by him if you can't.

There is a jlobgoczaebsmbmkwoxbn here.

There is a door to the critical room.

There is a door to room 9+10 here also.

Room 24

The room is covered in darkness. If you can find a way to get through it, read what is under "excited raichu is a nerd 2".

If you can't get through it, you can flee to room 91.

Room 25

There is a shield in this room. It gives you a $+2$ to combat power, but you need to use a hand to use it, and you can't use it with another shield.

There is a passageway to room 10100 here.

There is a passageway to room W_W>WZ here.

Pointless Button #2:

A passageway opens in front of you to room ertauqtgniv with a loud crash! However, the crash woke up the sleeping dragon in room 23, and you must fight him the next time you are in room 23. If you can't kill him, it's game over.

If you kill the sleeping dragon:

You plunder his treasure hoard and take 20 gold coins!

excited raichu is a nerd #2:

Glowing words appear on the walls.

yekehtsiairaxi

The lantern also reveals a secret passage to room no ur feet

excited raichu is a nerd #3:

When you kill the shadow hound, a staircase appears that leads to room $\sqrt {729}$, next time...

Combining the scroll:

A whirling, shadowy portal appears in the room and sucks you into room 15.

Answer 1

You start in room 16:

From there, you take the passage marked 13102213301233. By converting this from base 4 to base 10, you get 122322031. Repeating grants us 110221, then 1321, then 121, and finally 25.

In that room:

Grab the shield. You now have combat strength 3, using both hands. Now go to room 100100, which is binary for 20. There, grab the MAGIC LANTERN (backwards), then take the passage marked once, which is Spanish for 11.

This room:

Immediately sends you back to room 16. From here, go to room netter thewy (23, scrambled). Slay the dragon for +20 Gold Coins! Go to room 9+10 (19), and press the button. The dragon's dead, so that doesn't matter, but a passage to room ertauqtgniv (backwards and French for 24) opens. Take it!

Once here:

Use the MAGIC LANTERN. Glowing text tells you that IXARIA is the key. This will help with some of the scrambled messages. Use the revealed passage to get to no ur feet (Scrambled 14) There you get a die for +1 Combat Strength (Total 4). Go to 16. Go back to 23 and use the key to grab the "book you can't seem to open". You'll probably need it on the next floor :). Go back through 19, 24, and 14 to get back to 16 again.

Now, for a bit of cleverness:

Take the stairs back to room 7, and pay the dragon to get past (down to 10 coins now.) Navigate to room 10. Using IXARIA as a vigenere cipher key, you learn that this room contains a BATTLEAXE with the message "IT INCREASES YOUR COMBAT POWER BY THREE BUT YOU MUST USE A HAND TO HOLD IT". Trade out your rusty sword. You're now using both hands, and have total combat strength of 6. Navigate back to room 16, paying the dragon 10 coins again.

From here:

Use the key to find that room beiibyafxfdezqhime is actually room thirtysixoverthree, or 12. From there, go to room self-description, which is room 22 (because it has two two's). Using the key, you find that this room has half of a scroll. Passage thgienet takes you to room 18 (scrambled), then room 12, then head back to room 16.

From this room:

Go to room 25, then room W_W>WZ. I'm fairly certain this has to be room 17. Assuming this is right, there is a HALF OF A SCROLL (backwards) here, and a passage to The next room, which would be 18. Combine the two halves of the scroll, and you're whisked through a mystical portal to room 15

In this room:

Use the key to read the wall, "This is a boss room." Use your 6 combat strength to kill the shadow hound, then take the passage to room sqrt(729), which is room 27, on the next floor.

Things I'm not sure about:

If/How W_W>WZ is 17.
What the Critical Room is.
What the book you can't seem to open is for.