Blood Contract (血契約；chi-keiyaku) is a family introduced in BS60, possessed exclusively by the Contract card The PartnerKnight Bat, and the Purple cards with Contract Advent in the same set. The family is a representation to the contract which the wanderer Dan made with Bat in the lore, and since all the Purple cards with Contract Advent are technically a variant of Bat's power, they have the Blood Contract family as well.
Play Style[]
As currently all cards in this family are either a Contract card or a Purple card with Contract Advent, the deck highly revolves around the Advent mechanic. As part of the new series after the age of Rebirth cards, it also plays around high numbers of counters to differentiate themselves from the previous cards. Cards in this family are also always paired with the Blood Crystal family, often along with a tertiary family which is mostly irrelevant to the play style of the deck, so the play style may overlap with other Blood Crystal family cards.
The end goal of this deck is damaging the opponent with attacks while they are lacking cores, which can be done so by summoning The BlackSmokeDragon Fognir from the trash through the Advent effect of The DarkPurpleKnight Cheval-Bat, in which both cards are able to send cores to the trash. To do so, it is necessary to build up the player's own trash while also having The PartnerKnight Bat on the field. As such, it is advised to always put Bat in the starting hand, so that the player can proceed with early self-mill and count-boosting, as well as having an unremovable Advent base for the Advent cards in the deck. Due to the Advent conditions of the Blood Contract family cards, they are limited to only capable of adventing onto Bat or each other. The early game is about building up the trash and counters. With Bat's [Soul State][Contract Pre-Advent]/[Spirit][LV1][LV2] effect, both actions can be achieved at the same time.
The mid-game is about controlling the opposing board through removal effects, which is mainly the purpose of the Blood Contract family cards. While the other cards in the deck also have removal effects, some of them are used more for the purpose of summoning Spirit cards from the trash. As a Purple deck, it usually provides enough draws that the player does not need to dwell in this period, but before sending out Cheval-Bat, it is advised to reduce the opponent's life to three first.
When the player reaches seven counters or more, they are ready to advent Cheval-Bat. However, it is best to wait until nine counters, so that Cheval-Bat's Advent effect can summon Fognir from the trash. As Fognir's summon effect will give Cheval-Bat three symbols for the turn, there is not a need to summon many Spirits for enough hit points.
This deck has two very obvious weaknesses, one being that the removal effects do not pierce, the other being that the deck can easily submit to any form of effect-lock control, especially summon-effect lock. In terms of piercing, Magic cards which can treat themselves as colorless, such as Noir Shoot and Death Ataraxia, and those which can straight up ignore protection, such as Deathtament, can fill in the locks. On the other hand, most cards with summon-effect lock are Nexuses, so the player simply has to find the right timing to send out The Armor of Vainglory and The BloodAllianceThirteenMarquess Fallenhyde to deplete them. There is also the problem that Cheval-Bat's Advent condition is in either Attack Step, meaning that before it enters the field, the opponent still has one flash timing to prevent a lethal attack.
