As the Batman game from Knight Models gets bigger, I keep seeing people asking a very similar question.
"I really like (character) but who else works with them?"

To try and help out new players with their crew building and buying, I thought it would be a good idea to list each crew here with which models / packs work for them and any restrictions they may have. Specific restrictions will be in (brackets), as will the model version for those with different miniatures.
This should be easier for people than looking at each individual card online.

I will be referring to the different model types  like Leader and Free Agent. You can see what each means and how to build your crew using them here - Batman Crew Building
The plan is to keep this as a living post and add all monthly releases and any changes made.

BATMAN
Batman (All) - Leader
Nightwing - Sidekick
Green Arrow (Comic) - Sidekick
Red Hood - Sidekick
Batgirl - Sidekick
Batwoman - Sidekick
Com Gordon - Sidekick (SWAT Boss)
Robin (Drake) - Free Agent
Robin (Damien) - Free Agent
Huntress - Free Agent
Black Canary - Free Agent
Mr Freeze - Free Agent
Catwoman - Free Agent
Bane (Arkham) - Free Agent (Affinity)
- Poison Ivy (Arham) - Free Agent (Affinity Chain)
-- Harley Quinn (Comic) - Free Agent (Affinity Chain)
Talia AL Ghul - Free Agent (Affinity)
Swamp Thing - Free Agent (Affinity)
SWAT - Henchmen (Elite SWAT)
Echo SWAT (Loeb pack) - Henchman (Elite SWAT)
GCPD Detective (Loeb pack) - Henchman
Police Set 1 - Henchmen
Police Set 2 - Henchmen

GREEN ARROW
Arrow (CW) - Leader
Green Arrow (Comic) - Sidekick
Speedy - Sidekick
Black Canary - Free Agent
Huntress - Free Agent
Catwoman - Free Agent
Mr Freeze - Free Agent
Police Set 1 - Henchmen
Police Set 2 - Henchmen
SWAT - Henchmen (Elite SWAT)
Echo SWAT (Loeb pack) - Henchman (Elite SWAT)



LAW FORCES
Commissioner Gordon - Leader (SWAT Boss)
Commissioner Loeb - Leader (SWAT Boss)
Lieutenant Branden (Loeb pack) - Sidekick (SWAT Boss)
Batwoman - Sidekick
Batgirl - Sidekick
Catwoman - Free Agent
Mr Freeze - Free Agent
SWAT - Henchmen (Elite SWAT)
Echo SWAT (Loeb pack) - Henchman (Elite SWAT)
GCPD Detective (Loeb pack) - Henchman
Police Set 1 - Henchmen
Police Set 2 - Henchmen

WATCHMEN
These work a little differently to other crews. They can ONLY use models with the Watchman rank. These are -
Silk Spectre II
Ozymandias
Niteowl
Rorschach
Comedian

FREE AGENTS + UNALIGNED HENCHMEN
These models can be used with ANY of the Villain crews below apart from the listed exceptions.

Clayface - Free Agent (Not with Bane)
Scarecrow (Arkham) - Free Agent
Deathstroke (Origins) - Free Agent
Deathstroke (Comic) - Free Agent
Riddler - Free Agent
Lobo - Free Agent (Not with females)
Catwoman - Free Agent (Not with Joker or Two Face)
Mr Freeze - Free Agent
Victor Zsasz - Free Agent
Deadshot - Free Agents
Killer Croc - Free Agent (Not with Bane)
Soloman Grundy - Free Agent
Copperhead - Free Agent

Blackgate Prisoners - Henchmen
Blackgate Prisoners 2 - Henchmen
Lunatics - Henchmen

JOKER
Joker (Arkham + DKR) - Leader
Titan Joker - Leader
Harley Quinn (Arkham + Comic) - Sidekick
Mr Hammer - Sidekick (Circus Boss)
Clowns Starter - Henchmen (1 Elite Circus)
Clowns set 1 - Henchmen
Clowns set 2 - Henchmen
Clowns set 3 - Henchmen (1 Elite Circus)
Elite Clowns - Henchmen
Titan Clown - Henchman
Joker Gas - Objective

PENGUIN
Penguin - Leader
Gotham Penguin - Leader
Sickle - Sidekick (Penguin Boss)
Ivy (Arkham) - Free Agent (Affinity)
- Harley Quinn (Comic) - Free Agent (Affinity Chain)
Thugs Starter - Henchmen (1 Elite Penguin)
Thugs set 1 - Henchmen
Thugs set 2 - Henchmen
Thugs set 3 - Henchmen (1 Elite Penguin)
Titan Penguin - Henchman


TWO FACE
Two Face - Leader (Gangster Boss)
Lieutenant Branden (Loeb pack) - Sidekick (SWAT Boss, Corrupt)
Twowt Starter - Henchmen
Two Face Crew set 1 - Henchmen
Two Face Crew set 2 - Henchmen
Mobsters set 1 - Henchmen (Elite Gangster)

BANE
Bane (All) - Leader
Ivy (Arkham) - Free Agent (Affinity)
- Harley Quinn (Comic) - Free Agent (Affinity Chain)
Mercs Starter - Henchmen
Mercs Set 1 - Henchmen

POISON IVY
Ivy (Arkham + Comic) - Leader (Plants Boss)
Swamp Thing - Sidekick (Plants Boss)
Harley Quinn (Comic) - Free Agent (Affinity)
Plants starter - Henchmen (Elite Plants)

LEAGUE OF SHADOWS
Ra's Al Ghul (Arkham + DKR) - Leader (Ninja Boss)
Nyssa Al Ghul - Sidekick (Ninja Boss)
Talia Al Gul - Sidekick (Ninja Boss)
Bane (DKR) - Sidekick
Scarecrow (DKR) - Free Agent
Ninjas Starter - Henchmen (Elite Ninja)
Ninjs set 1 - Henchmen (Elite Ninja)
Bane Mercs Starter - Henchmen
Bane Mercs Set 1 - Henchmen


BLACK MASK
Black Mask - Leader (Gangster Boss)
Lieutenant Branden (Loeb pack) - Sidekick (SWAT Boss, Corrupt)
Mask Thugs starter - Henchmen
Mask Thugs Set 1 - Henchmen
Mobsters set 1 - Henchmen (Elite Gangster)



ORGANISED CRIME
Red Hood - Sidekick
Gotham Penguin - Sidekick
Commissioner Loeb - Sidekick (SWAT Boss, Corrupt)
Lieutenant Branden (Loeb pack) - Sidekick (SWAT Boss, Corrupt)
Mobsters - Henchmen (Elite Gangster)

All of these can be found on the Knight Models page.
Let me know if you spot any mistakes.

- Hendybadger