To see the chapter similar to this title, see Blood Contract.
Also known as Blood Contract, this document is a written agreement between two parties, as seen in Fire Emblem: Radiant Dawn and is used mainly in the sense of trickery and deceit to get what one wants.
This document is produced by two parties, one who writes the document and the other who signs it. Failure to perform what the document asks inflicts a curse on the person or country of said person, thus making it a deadly document not only for a single person but many. Due to this, the party signing the document is usually tricked into it, mainly by the Begnion Senate to get what they want. The person who signs the document has a visual brand on their forearm (usually) closely resembling that of a Branded.
If one fails the pact, the curse will kill a person for every day that passes until the pact is destroyed or every citizen in said country or state is killed.
To destroy the pact, one must kill one of either party who produced it and destroy of the paper itself. Throughout Fire Emblem: Radiant Dawn, Pelleas and the Dawn Brigade try to discover this mean of destroying the pact because of his active Pact.
 Known Blood Pacts
Ashnard arose to power of Daein in Fire Emblem: Path of Radiance when he tricked his own father, the 12th king of Daein, into signing a Blood Pact with a traveling wise-man. Ashnard waited until the effects of the blood pact slowly wiped out everyone in line to succeed the throne and then personally killed his father, making him the 13th king of Daein. Because of these lunatic actions, Ashnard is often referred to as the "mad king of Daein."
During Fire Emblem: Radiant Dawn, it's revealed that a Raven King before Naesala was tricked by Lekain, a very powerful Senator, to sign a Blood Pact in order to save his country. The former Raven King realized too late what the effects of the pact do, and hundreds of ravens, along with his child and wife, were found dead; this explains Naesala's rise to the throne. During Radiant Dawn, Naesala, taking the pact on as the new king, is forced to abandon the Laguz Alliance and nearly killed the Laguz Tribes within it. It's not until later in the game that Naesala reveals this pact and the burdens that it contained. Naesala does this when everyone is turned to stone, temporarily removing the effect of the pact because those turned to stone can not die. He takes this oppurtunity to rejoin the Laguz Alliance with his apology. At the Tower of Guidance, Naesala is able to find the pact and destroy it, removing its effect on his country. If he is not present, Sanaki will hold it for him.
After Pelleas returns to the throne of Daien, he, along with the Dawn Brigade, take back the country from Begnion and begins to reconstruct the country under his name. Later in the game, however, he randomly announces an attack on the Laguz army heading for Begnion. When asked why he would announce a war shortly after his independence, Pelleas would not give an answer.
It is later revealed that Lekain, with help of Izuka, Pelleas' fake advisor, tricked Pelleas into signing a pact so that Daien could act as a bumper for Begnion in the new war. Pelleas, when revealed to Micaiah, does all he can to learn how to destroy the pact. If it is before your second play through, Pelleas will kill himself because he believes it will immediately destroy the pact. He will ask Micaiah to perform the task but will have Tauroneo do it if declined. If its on your second+ play through, Pelleas can be talked out of it and will later learn through Kurthnaga that the death of the other party, Lekain, can also work.
At the Tower of Guidance, Micaiah will destroy the pact after Lekain's death.