Palace of the Four Sword

The Palace of the Four Sword is a bonus dungeon included in the GBA version of The Legend of Zelda: A Link to the Past, accessed by entering the eastern side of the Dark Pyramid. However, the player can only access past the first room of the dungeon after completing the multiplayer The Legend of Zelda: Four Swords, the extra game bundled in the cart in which 2-4 players must search through puzzle-ridden dungeons to hunt down the Wind Mage Vaati, who has captured Princess Zelda. The dungeon contains many dangerous bosses, even more difficult than the original bosses of A Link To The Past (critically acclaimed as some of the most difficult in Zelda games to date).

The Dungeon
The aim of the dungeon is to acquire the four Aspects of the Four Sword (The Green Sword, The Red Sword, The Blue Sword & The Purple Sword) to create The Four Sword, in order to confront the final boss. The four aspects are found under the guard of four bosses in the dungeon, and very difficult bosses at that. After collecting all four aspects, the player can challenge the final boss of the dungeon, four doppelgangers of Link himself. Completion of the dungeon allows for a new ending scene, and unlocks a Quest Log in order to view certain stats and records in the game.

Arrghus II
Guarding the Green Sword, a more powerful version of the original Arrghus in the game, a large and rather grotesque jellyfish surrounded by smaller jellyfish. Use the Hookshot to pick the small jellyfish off, and then while Arrghus is bouncing round the room, attack him. He takes 9 hits from the Lv 4 Golden Sword to down.

Helmasaur King II
Again, a more powerful version of the boss guarding the Palace of Darkness. Notably the most difficult boss of the original game in his first form, and no easier the second time round. By using Bombs/the Magic Hammer to remove his mask, you can then hack away at him with your sword. Again, 9 hits from the Golden Sword, and then he will grow another mask. This time, remove the second mask, and then shoot a single Silver Arrow into the eye revealed on the Helmasaur King II; don't bother with the sword, it won't work.

Mothula II
One of the simpler bosses to kill, but by far more difficult than the first two. Mothula II will split itself into 3 different Mothulas upon arriving, which will all attack and fire bees at you. A fake Mothula II can be easily destroyed in a couple of hits, but the original will then create more. There is no real strategy; just try to find the original Mothula II, and hack at him. 8-10 hits from the Lv 4 Golden Sword should deal with him.

Blind II
Another improved version, this time of Blind the Thief. Get him in the head 3 times with your sword (while avoiding the highly dangerous laser attack he utilises), and Blind's head will detach. Now, attack the head and it will bounce around the room; try and make it bounce back on to Blind's body, and it will rejoin him. Repeat the first step, and two heads will detach. Bounce them both back to the body, and then repeat the first step again. Three heads will now detach; the end is near. Bounce all three back at Blind, and he will finally die.

The Four Links
Four doppelganger Links; by far more difficult than all the first four bosses combined. They will attack one at a time, allowing for a less frantic battle. The first Link is rather easy, and can be disposed of in 8 hits; make sure to avoid the attacks, which should be easy. The second Link is nearly identical, except he can use the Whirlwind Spin attack. As long as you time your movements correctly, still not much trouble. Another eight hits, and he's down. The third is slightly more powerful; he'll use a dangerous dive attack that is difficult to detect and then dodge, and hits for a lot of damage. 8 more hits leave the final Link, and the Final Battle. This one employs the attacking strategies of all three previous Links, plus an even more dangerous and quick lunge attack; plus, it takes 16 hits to beat him!

Rewards
For completing the Palace of the Four Sword, the player is granted the ability to view a Quest Log on the pause screen; this shows various data about the player's status in the game. Arugably not sufficient for such an arduous and challenging dungeon.