Despite being hidden in the shadows for many, the psychological horror Eternal Darkness: Sanity's Requiem remains one of the more interesting and eerie thrillers on GameCube, and perhaps in modern gaming. With this obscure horror game, Developer Silicon Knights brought a number of innovations, putting a neat twist on the action and horror genres.

Among these are the dynamic, mix-and-match system of magic and the rich, ominous narrative that spans over two millennia. The most interesting feature, however, is the game's Sanity Effects mechanic. This feature brings a slew of unsettling and jarring visuals along with in-game alterations that haunt and generally mess with the player. These range from fake error messages to shrinking character models.

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It's perhaps not surprising that this cryptic title offers a bounty of interesting secrets, details, and easter eggs that have eluded even most of the few who have discovered this GameCube hidden gem.

10 Health Depletes In Place Of The Sanity Meter If Depleted

Alex in dark mansion with depleted sanity meter in Eternal Darkness

Sanity is a critical element in Eternal Darkness, not just because of the spooky and amusing Sanity Effects, but also because it serves as an extra lifeline. The game is rather subtle about revealing one mechanic involving health and sanity; to the point where it has eluded many players.

When a character's Sanity Meter has been fully depleted, looking at a foe or picking up a triggering item will begin to whittle down a player's health instead of sanity. This can become dangerous, as players will be left more vulnerable with the pile-on of Sanity Effects along with health dwindling more quickly.

9 Pious' Face Shows After The Peter Jacob Chapter

Gamecube Eternal Darkness Sanity's Requiem Skeleton Gladiator Pious

The calamitous ninth chapter in Eternal Darkness features a field reporter in a gripping World War I setting. This already unsettling scene, which takes place in the Cathedral-turned-hospital, remains eerie after its ending when a certain condition is met.

This spooky easter egg initiates when keeping the game idle for at least five minutes with Alex, while her sanity is left at a low level. When this happens, the creepy, decrepit face of Pious will appear on the screen, complemented by the usual cries and laugher that comes with Sanity Effects.

8 A Useful Shortcut in Ellia's Chapter

Ellia at temple offering with candles in Eternal Darkness

Eternal Darkness wastes no time spooking its players with a second chapter wrought with things that go bump in the night inside a creepy temple setting. While navigation here can be a bit tricky, there is a handy shortcut that players can exploit to bypass nearly half of the stage.

At the beginning of the chapter, take a hard right with Ellia rather than examining the statue, and go through the door on the right side. This will lead to a later portion of the temple, skipping a decent chunk of the chapter.

7 The Elephant Gun

Eternal Darkness Elephant Gun on menu screen select

There is quite a wide range of unique weapons — which makes sense given the vast span of 2,000 years Eternal Darkness entails. One particularly amusing weapon is an old-school boomstick known as the Elephant Gun. It's a cool novelty to be sure, though it can also do quite a bit of damage when both barrels are fired simultaneously.

Unlike most weaponry in the game, this one is often missed as it requires a secret action in order to obtain. To get it, head upstairs in Edward's chapter (chapter ten) and wait for the vampire to show in the master bedroom. Save the servant and speak with him to secure the Gun Cabinet Key. Then head to the smaller bedroom and unlock the gun cabinet, where this awesome weapon will be waiting.

6 A Trick To Reload Instantly

Alex looking to side holding large rifle in basement in Eternal Darkness

Reloading the mostly antiquated weapons can be a hassle in Eternal Darkness, especially when being harassed by zombies and vampires. Luckily, there's a unique exploit involving the menu to bypass this added time of vulnerability. This is a nifty trick that few players have managed to notice.

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After being depleted of ammo, press "start" and select the gun being used. Then select "mix" and click on the ammunition that goes with the weapon. After returning to the on-screen action, players will find that the gun is instantly loaded absent the reload animation.

5 The Frightening Bathtub Scene

Eternal Darkness Alex Bathtub Scene dead in blood

While Eternal Darkness lays it on thick in terms of eerie atmosphere and themes, straight-up horror-style jumpscares are few and far between. However, there is one particular scene almost sure to coax some startled seat-jumping; and perhaps one of the scariest moments in modern gaming.

After the end of chapter three, head to the second floor with Alex and enter the bathroom. Here, there will be a "point of interest" in the bathtub. Look inside, and players will be treated to a harsh, creepy shot of a pale Alex lying dead in a tub of blood — fittingly complemented by a loud shriek.

4 The Enchanted Gladius

Michael looking at Pious picture in temple in Eternal Darkness

The Enchanted Gladius is a secret weapon that requires actions from the player in three separate chapters, which carry over. This potent blade can finally be obtained in chapter 11.

First, in chapter four, go through the door that's opened with an enchanted Ram Dao, atop the first ladder. The Ruby Effigy lies in the middle of a room guarded by Trappers. This will be exchanged for the Sapphire Effigy in chapter eight. Cast a Reveal Invisible spell in the room with the lava floor and invisible bridge. The Effigy will be in a crevasse in the wall. In chapter 11, fight through a pit of worms and a Damage Field in the hallway past the Tome of Eternal Darkness. The Emerald Effigy will be waiting.

Finally in this same chapter, go to the room near the mysterious obelisk, and put the three effigies on the ledges under the pictures. Ruby matches with the Scholar, Sapphire goes with the Warrior, and Emerald goes under the Sorcerer. The Enchanted Gladius will be the hard-fought reward.

3 Eternal Mode

Lindsey firing at reaper with full sanity meter in Eternal Darkness

Eternal Darkness' campaign is on the short side, though studio Silicon Knights bumps up the replay value quite a bit by offering new features after multiple game completions.

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Beating the game three times on the same save file will unlock an amusing God mode called "Eternal Mode," where players are granted infinite health, magick, and sanity.

2 The Purple Rune

Eternal Darkness Mantorok Rune in temple opening

The unique spell system is one of the more interesting aspects of Eternal Darkness, but as it happens, many players end up missing the best of the four "magick" colors — the purple or "Mantorok" spells. These powers are significant as the spells are among the best in the game, and eclipse the other three (red, blue, and green), which are locked in a rock-paper-scissors advantage system.

The sixth chapter in the game, featuring archaeologist Edwin Lindsey, holds a secret area in which this coveted Rune can be obtained. Go to the floor with the gold statue and reach the machinery revealed after dispelling of the magick fields.

There will be a small hole that requires a trapper to venture through. Use the Summon Trapper spell to access this area, and cross a bridge, bypassing the two Horrors and stand on a switch with a purple Rune. The Mantorok Rune can now be accessed.

1 The "Real" Ending

Eternal Darkness alternate ending cutscene with Ulyaoth

Similar to "Eternal Mode," there's another neat unlockable that triggers after a trio of game completions. This one, however, requires players to defeat the final boss with each of the three Rune alignments on the same save file.

These alignments are chosen all the way back in the first chapter, and cannot be changed, so the game must be finished all three times, with each option selected. Doing so will unlock this revealing new cutscene.

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