Here is the full list of all 93 Renfield: Bring Your Own Blood achievements.
Finish Livespring High using Cheerleader once.
Defeat Bella Lobo using Teddy Lobo once.
Finish a stage with Mark.
Summon Familiars 10 times.
Summon Familiars 5 times.
Complete 10 challenge rooms.
Summon a Familiar for the first time.
Complete 3 challenge rooms.
Complete 5 challenge rooms.
Collect a total of 20000 Big Bugs
Use 1000 powerups
Collect 1000 Moneybags
Retrieve Escapee
Kill a total of 300000 enemies
Consume 10 Egg Heads within a single run
Finish 7 consecutive rooms without being damaged
Finish 12 consecutive rooms without being damaged
Collect a total of 10000 Big Bugs
Collect a total of 5000 Big Bugs
Collect 500 Moneybags
Use 600 powerups
Collect 500 artifacts
Kill a total of 150000 enemies
Finish a Boss fight within 50s
Use 6 unique powerups
Finish 3 consecutive rooms without being damaged
Finish a Boss fight within 150s
Finish a Boss fight within 100s
Kill a total of 75000 enemies
Deal 1,000,000 total damage using weapons
Finish 12 rooms with less than 20HP
Use 300 powerups
Collect 200 artifacts
Collect 200 Moneybags
Retrieve Cheerleader
Consume 7 Egg Heads within a single run
Deal 500,000 total damage using weapons
Finish 5 rooms with less than 20HP
Collect 75 artifacts
Deal 200,000 total damage using weapons
Consume 5 Egg Heads within a single run
Die ten times
Finish 3 rooms with less than 20HP
Die five times
Die one time
Use 1 unique powerup
Use 3 unique powerups
Retrieve Dollymop
Kill a total of 500 enemies using Special Attacks
Kill a total of 1000 enemies using Special Attacks
Kill a total of 1500 enemies using Special Attacks
Finish a level without picking up a powerup
Finish 4 levels without picking up a powerup
Finish 7 levels without picking up a powerup
Finish a stage with Rebecca Quincy.
Finish 3 stages with Rebecca Quincy.
Finish 5 stages with Rebecca Quincy.
Defeat Dracula using Robert once.
Defeat Dracula using Robert 3 times.
Defeat Dracula using Robert 5 times.
Defeat Bella Lobo using Teddy Lobo 3 times.
Defeat Bella Lobo using Teddy Lobo 5 times.
Do the Kill Route using Dracula 3 times.
Do the Kill Route using Dracula 6 times.
Do the Kill Route using Dracula 9 times.
Defeat 1 Boss using Sister Charlotte.
Defeat 3 Bosses using Sister Charlotte.
Defeat 5 Bosses using Sister Charlotte.
Finish 3 stages with Mark.
Finish 5 stages with Mark.
Finish Livespring High using Cheerleader 3 times.
Finish Livespring High using Cheerleader 5 times.
Finish a stage with Sun-Kissed Dracula using Sunlight 3 times.
Finish a stage with Sun-Kissed Dracula using Sunlight 6 times.
Finish a stage with Sun-Kissed Dracula using Sunlight 10 times.
Finish Dracula's Castle with 4 different characters.
Finish Dracula's Castle with 8 different characters.
Finish Dracula's Castle with 12 different characters.
Defeat Dracula using 3 different characters.
Defeat Dracula using 5 different characters.
Defeat Dracula using 7 different characters.
Use the special attacks of at least 5 different characters at least once.
Use the special attacks of at least 10 different characters at least once.
Use the special attacks of at least 15 different characters at least once.
Finish Murder Room with 4 different characters.
Finish Murder Room with 8 different characters.
Finish Murder Room with 12 different characters.
Reach Wave 70 in Endless Mode with 3 different characters.
Reach Wave 70 in Endless Mode with 6 different characters.
Reach Wave 70 in Endless Mode with 9 different characters.
Complete one level in Nightmare mode.
Complete three levels with at least 3 different Nightmare Conditions.
Complete five levels with at least 3 different Nightmare Conditions.