Journey Into Darkness
"I will show you what happens to those souls...who think they can look into the eyes of the Jackal..."
is a Sonic the Hedgehog Fan Fic
written by Surenity
. Though it takes place after the events of Sonic X
it blends elements from Sat Am
, Adventures of Sonic the Hedgehog
, and the Sega Genesis
Tails hasn't been able to forget Cosmo after having to put an end to her life himself, and is still in deep mourning. However, hope arrives in the form of Sevag the Jackal
, a necromancer from Sandopolis
on Angel Island, as he offers to perform a resurrection ceremony using the seven Chaos Emeralds and the Master Emerald...for a price of course. Against the advice of his friends, Tails embarks on a journey for the seven chaos emeralds, a journey that brings him deeper and deeper into the dark side as Tails faces his inner demons. Little does he know, he's not the only one after the emeralds...
Originally written in 2006 and posted on Fanfiction.net, it received a 2008 rewrite and was posted on deviantArt. It can be read here: 
- Arm Cannon: Tails' roboticized mother has one.
- Berserk Button: Tails' berserk button is activated when Shadow cruelly reminds Tails that he killed Cosmo, and that Shadow isn't to blame. (Tails harbors quite a grudge against Shadow for the time he tried to kill Cosmo.)
- Bittersweet Ending: Tails is able to bring back Cosmo...but at the cost of his mother.
- Break the Cutie: Pretty much has already happened to Tails by the start of the story.
- The Cameo: Metal Sonic, Decoe and Bocoe, and Scratch and Grounder are seen floating in glass tubes in Dr. Eggman's lab.
- Companion Cube: Cream was using a Chaos Emerald as one.
- Continuity Nod: All over the place, and to several different continuities at that.
- The Dark Side
- Deal with the Devil: Or the Jackal, rather.
- Face-Heel Turn: The inner turmoil Tails is facing turns him into one, as his allegiance towards Sevag grows.
- Flanderization: Of Cream.
- Flash Back: Chapter 9 is a flashback to the episode of Sonic X where Cosmo and Tails were trapped inside a cave together. It's relavant to the plot.
- Heartwarming Orphan: Unlike almost every Sonic-related thing ever, this story acknowledges that Tails is an orphan, and uses that to deepen his character.
- The Renfield: Tails, to Sevag
- I Am Your Father: Tails' roboticized mother appears later on, and it turns out Sevag the Jackal was an old boyfriend of hers (though he's not Tails' biological father).
- "I Know You're in There Somewhere" Fight: After Tails reaches his evil super form, Cosmo tries to talk sense into him and bring him back.
- Interspecies Romance: Tails and Cosmo, of course.
- Melancholy Moon: Tails howls at it, a side effect of his dark carnal side showing itself.
- Mind over Matter: One of Sevag's powers.
- Necromantic: Tails wanting to bring Cosmo back from the dead, and Shadow wanting to gather the emeralds before Tails so he can have Sevag bring back Maria.
- Nostalgia Level: Robotropolis in Chapter 8. Tails even fights Metal Robotnik, the final boss from Sonic the Hedgehog 2.
- Not So Different: It turns out Sevag had a very similar experience as Tails, losing his true love who sacrificed herself. That love was Tails' mother. And Tails seems to be headed down the same dark path Sevag took...
- Puppy Love: Tails and Cosmo
- Resurrected Romance: The story ends with Cosmo and Tails finally being happily reunited.
- Screw the Rules, I Have Supernatural Powers!: Sevag
- Sealed Evil in a Can: It turns out that Sevag was sealed away in Sandopolis for being responsible for destroying the echidna race by unleashing Chaos (the Big Bad from Sonic Adventure). The seal was broken by none other than Shadow the Hedgehog.
- Shout-Out: The author being an old-school Sonic fan, there are plenty to go around:
- Sonic saying "I'm waaaiiitttinnnggg..." and inviting Tails to go out for chili dogs.
- Mentions of item boxes hidden in palm trees in Chapter 5.
- Dr. Eggman asking Tails if he's 'snooping as usual'.
- The pyramid Sevag was trapped in actually is Sandopolis Zone: Act 2 from Sonic And Knuckles.
- Super-Powered Evil Side: Tails, after gathering the Chaos Emeralds and using their energy.
- Talking to the Dead: Tails talks to the plant which sprouted from the seed Cosmo left behind after her death as if it were Cosmo.
- Title Drop: A few times.
- Too Dumb to Live/Idiot Ball: Yes, Cream, go on, use a chaos emerald for one of your tea parties, i'm sure that's not going to lead to any consequences.
- Villain Decay: Dr. Eggman is trying to reverse the villain decay that happened to him in Sonic X by being more like how he was in '"Sat Am'', rebuilding Robotropolis and planning to roboticize more animals.
- Woobie, Destroyer of Worlds: Tails almost becomes this at the climax, though, thanks to Cosmo, it just barely averted.
- You! Exclamation: When Tails first sees Shadow, and later when Shadow sees Sonic.