ゼルダの伝説：神々のトライフォース
The Legend of Zelda: Triforce of the Gods

There are strong geographical similarities between the Light and Dark Worlds, but the details are drastically different. The Dark World is crawling with twisted monsters the likes of which Link has never before seen. The ground, air, and water are all befouled, the rocks look more like skulls, and, thanks to the absence of several bridges (both natural and man-made) and the presence of additional obstacles, it's considerably more difficult to get around. Link is currently restricted to a small section in the eastern part of the world (plus the section of mountain he could reach earlier, from the warp tile there). All other areas are inaccessible due either to missing bridges or to strange purple pegs that are unaffected by anything in Link's arsenal. Meanwhile, there are now more and tougher guards and monsters in the Light World, possibly an effect of the power seeping from the Dark World.

Near the base of the pyramid is a crack in what looks like a sealed doorway, but even Bombs have no effect.

After exploring for a while, Link finds a sign by the lake at the river's source, one of the few areas accessible in the Dark World.

Toss something into the interesting circle of stones in the pond (I recommend the sign for bonus irony points). A large catfish surfaces with a rumble...

The catfish tosses at Link a large golden coin with a wavy pattern engraved on it.

Using the Shake magic eats up Link's magic meter (32 magic for one use), but it can be worth it. When he uses it, Link spins around three times, then leaps into the air and plunges his sword into the ground. Shockwaves radiate out, shaking everything and affecting nearly all non-flying enemies. Some die outright, some are rendered helplessly immobile for a fairly long time, and many are permanently transformed into frail and stupid monsters that look like moving vegetables with faces.

Earthquakes are caused by catfish, according to Japanese folklore.

Link heads to where the Eastern Temple would be in the Light World. Instead of a series of cliffs, the area has what amounts to a hedge maze. Nearby is small building with a plant-man inside.

As Link navigates through the hedge maze, a monkey starts following him.

Yeah, whatever. It could come in handy, and 10 rupees is practically nothing.

Before long, they reach the temple. The entrance is sealed, and there are several large monkey statues around. Hmm...

It looks like there's no choice. Fortunately, money isn't too difficult to come by, and 100 won't break the bank.

The monkey hops around, hitting a few hidden and unreachable switches, and the entrance opens...

Here in the Dark World, the temples are larger, the music and decorations are creepier, the monsters are tougher, the layouts are more confusing, and the quirks are quirkier. This particular one has numerous dark rooms and seemingly invulnerable headless turtles, and introduces tiles that warp Link between different rooms, collapsing floors, odd... braziers?... that are immobile and invincible and shoot fireballs at Link at regular intervals, strange barriers sticking out of the floor, and jellyfish that periodically electrify themselves, shocking Link if he tries to hit them with melee attacks. It also has a (one-time only) puzzle that requires Link to shoot an arrow into the eye of an oddly-colored cyclops statue.

Not far into the area, Link finds a telepathic tile:

The big key is harder to get to than ever before, and involves bombing the floor and jumping in. The big chest, on the other hand, involves bombing through a wall, but is otherwise relatively straightforward, and contains...

Yes, the original really is that silly...

The Magical Hammer (as it's called in the menu screen; let's forget the lame joke) can pound down the weird floor barriers in the temple (and some other indoor areas), the purple pegs outside in the Dark World, and the wooden stakes in the Light World, allowing Link to pass them. It also works as a weapon, causing twice the damage (usually) of the Master Sword, but is too slow and short-ranged for effective use on most enemies. More usefully, it flips over the turtle monsters, making them vulnerable to attack until they manage to flip back over. As a fun side effect, frozen enemies killed with the Hammer nearly always drop magic jars (and shatter in a single hit).

After fighting off hordes of turtles in a series of dark rooms, Link finally reaches the boss's lair. It looks like a demonic scorpion with a protective mask on its face. Hitting the mask with the Hammer or with Bomb explosions damages it, until it breaks off completely, revealing a large, vulnerable-looking, green something in the beast's forehead... it's clobbering time! The boss moves faster without its mask, but it can't take much more of a beating, so Link finishes it off quickly. It does the usual explode-and-drop-a-heart-container thing, and then a crystal falls into the middle of the room. Link picks up the crystal and finds that one of the seven maidens is trapped inside.

The style of the last line feels a bit different from the rest of the conversation, so between that and the fact that every one of the maidens says exactly the same line, it's probably supposed to be a traditional prayer or blessing.

As always, Link is fully healed and does his little victory spin. His map now also shows where the other six maidens are...