Each card among your given choices belongs to exactly one of the eight sequences described. These are:

Sequence 1: The number of words in the rules text decreases by one. (Unsummon has seven words in its rules text, Knighthood has six, and so forth.)

1. Unsummon
2. Knighthood
3. Vitalize
4. Sacred Nectar
5. Stone Rain

Sequence 2: The number of tokens created by the card decreases by one. (Conqueror’s Pledge creates six tokens, Skittering Invasion creates five, and so forth.)

1. Conqueror’s Pledge
2. Skittering Invasion
3. Revel of the Fallen God
4. Feral Incarnation
5. Raised by Wolves

Sequence 3: Each card’s mana cost can be found in the previous card’s rules text.

1. Dark Impostor
2. Vein Drinker
3. Priest of Iroas
4. Rune-Cervin Rider
5. Sundering Growth

Sequence 4: Each card’s flavor text refers to a number, and these numbers decrease by one. (Hada Freeblade’s flavor text mentions the number eight, Krark-Clan Ogre mentions the number seven, and so forth.)

1. Hada Freeblade
2. Krark-Clan Ogre
3. Magnetic Flux
4. Mad Prophet
5. Grounded

Sequence 5: The number of colors for each card decreases by one. (Dune-Brood Nephilim is four colors, Hazezon Tamar is three colors, and so forth.)

1. Dune-Brood Nephilim
2. Hazezon Tamar
3. Giant Solifuge
4. Willow Faerie
5. Memnite

Sequence 6: Each card’s mana cost may be found in its own rules text, and their converted mana costs decrease by one.

1. Stonehorn Chanter
2. Dementia Bat
3. Hunting Triad
4. Electropotence
5. Courier’s Capsule

Sequence 7: Each card costs a certain number of mana of a single color, and all converted mana costs decrease by one.

1. Rushwood Elemental
2. Elemental Appeal
3. Fated Infatuation
4. Celestial Flare
5. Stabbing Pain

Sequence 8: The number of “X”s in the rules text of each card increases by one. (Aurelia’s Fury has one “X” in its rules text, Scorched Earth has two, and so forth.)

1. Aurelia’s Fury
2. Scorched Earth
3. Myr Battlesphere
4. Death Cloud
5. Liliana of the Dark Realms