The Rite of Silent Binding
This will summon a dead loved one. To be performed during the waning crescent. A mirror, three black candles, and silence are required. Speak no words. Let the ink dry on the parchment before sealing.
Consequences: Loved ones may disappoint you. And you may disappoint them. Especially a parent. Especially if you didn't become a lawyer.
The Offering of the Hollow Flame
This will summon a dead enemy. Burn herbs collected under moonless skies. Whisper the names of the forgotten into the ash. Leave nothing behind.
Consequences: You may vomit blood, laugh uncontrollably or start listening to exclusively Iron Maiden. Oh, and also your enemy may strike you.
The Ritual of Ningal
This will release the absolutely vile spirit of Humbaba. You should not do this one under any circumstances. But if you choose to, you must say the spell (which you can buy on my store). I then recommend you place it in a cryptex (also available on my store for $49.99 for a limited time) so that no one may find it. It's very powerful!
Consequences: Humbaba may choose to overtake the performer of the ritual. If he does this, you may find yourself waking up very late, staring off into space, laughing maniacally, twitching and drinking gallons of milk.
To Undo the Ritual: You must find a group of pure souls who must utter the spell (which you've placed in a cryptex!) in reverse. Like, say the words in reverse order. To be super explicit if this isn't clear, if the spell were "Hi, my name is Bob." You would say "Bob is name my hi". Obviously that's not the spell because you have to buy the spell on my store. And it's not cheap. But it is worth it.