Apparently Bridges

|Overlord of Misery|0|FBP1|Fiend/Effect|Dark|4||1500|1500|If this card is the only card face-up on your side of the field, it's original ATK and DEF becomes 3000. If this card is sent to the Graveyard, Special Summon it, and it's ATK and DEF is reduced by 500; if this card is Special Summoned this way, banish it when it's removed from the field.|

|Ominous Harvester|1|FBP1|Fiend/Effect|Dark|4||1400|1850|During your Standby Phase, if there is a Normal or Quick-Play Spell Card at the top of your Graveyard; return it to your hand. When a Normal or Quick-Play Spell Card is activated, increase this monster's ATK by 400 until the End Phase.|

|Unraveler of Virtues|2|FBP1|Fiend/Effect|Fire|2||1200|1000|When your opponent takes Effect Damage, you can Special Summon this card from your hand. While this card is face-up, whenever your opponent takes effect damage, increase the ATK of 1 monster you control by 300.|

|Adamant Atrocity|3|FBP1|Fiend/Effect|Fire|3||1300|1500|If your opponent's Life Points are below 3000, double the original ATK and DEF of this card. If your opponent activates a Trap Card, Special Summon this card from your Graveyard.|

|Darascythe Fiend|4|FBP1|Fiend/Effect|Earth|4||1600|300|If your opponent controls a WIND or WATER Monster, this card can attack your opponent directly. Once per turn, you can return up to 5 of your banished Spell or Trap Cards to your deck. This card is unaffected by Field Spell Cards.|

Darkest Hour wrote:

|Overlord of Misery|0|FBP1|Fiend/Effect|Dark|4||1500|1500|If this card is the only card face-up on your side of the field, it's original ATK and DEF becomes 3000. If this card is sent to the Graveyard, Special Summon it, and it's ATK and DEF is reduced by 500; if this card is Special Summoned this way, banish it when it's removed from the field.|
Good survivor card.

|Ominous Harvester|1|FBP1|Fiend/Effect|Dark|4||1400|1850|During your Standby Phase, if there is a Normal or Quick-Play Spell Card at the top of your Graveyard; return it to your hand. When a Normal or Quick-Play Spell Card is activated, increase this monster's ATK by 400 until the End Phase.|
Does this stack? I.e. if you had 3 Spells in a row you could add them all to your hand? Anyway very cool card

|Unraveler of Virtues|2|FBP1|Fiend/Effect|Fire|2||1200|1000|When your opponent takes Effect Damage, you can Special Summon this card from your hand. While this card is face-up, whenever your opponent takes effect damage, increase the ATK of 1 monster you control by 300.|
Perfect for FIRE. The epitome of FIRE decks. Love it.

|Adamant Atrocity|3|FBP1|Fiend/Effect|Fire|3||1300|1500|If your opponent's Life Points are below 3000, double the original ATK and DEF of this card. If your opponent activates a Trap Card, Special Summon this card from your Graveyard.|
It is good, just can't find a deck where it "fits". Maybe FIRE?

|Darascythe Fiend|4|FBP1|Fiend/Effect|Earth|4||1600|300|If your opponent controls a WIND or WATER Monster, this card can attack your opponent directly. Once per turn, you can return up to 5 of your banished Spell or Trap Cards to your deck. This card is unaffected by Field Spell Cards.|

Sensing combo with Infiltrator cards. The banished return effect seems kind of random.