Justin Baldoni‘s beef with Blake Lively is spreading beyond his former co-star … because he’s now targeting Marvel and asking the superhero company to hand over some Deadpool docs.

Here’s the deal … Justin claims Blake’s husband Ryan Reynolds mocked him in the latest ‘Deadpool’ movie and he warned Disney and Marvel to hold onto all the docs related to the characters Ryan plays in “Deadpool & Wolverine” … but last week, Marvel filed a motion to quash Baldoni’s subpoena.

Now, Baldoni is responding to Marvel’s move … and in new legal docs, obtained by TMZ, Justin doubles down on his assertion that the Nicepool character is a mocking depiction of him.

As we reported … Baldoni thinks this relates to him because Blake accused him of sexually harassing and fat-shaming her postpartum body on the “It Ends With Us” set. As for the feminist line, it seems Justin thinks it’s a jab at him touting himself as a feminist and ally during the press run for the flick.

Marvel claims the movie characters and jokes are irrelevant to Baldoni’s cases against Blake and Ryan … and they claimed Nicepool is just an expression of opinion, not fact.

But Baldoni says Nicepool absolutely is relevant to his case … and he says he needs the Marvel docs so he can figure out if there’s something in there he can use to prove Ryan’s alleged malice.

For his part, Ryan is trying to get Baldoni’s lawsuit against him thrown out of court … saying Justin is just upset about Nicepool because he’s “thin-skinned.”