Was Val really that difficult on movie sets?

I guess the ego did get out of control for awhile, there's that clip on youtube where they say Val Kilmer was rude to the Japanese fans during Val's Batman Forever press tour in Tokyo..and that he was fairly rude and condescending during filming of Island of Dr. Moreau.
I can certainly see how it happens, he's in bigger and bigger films..and the stress of trying to keep the quality of the work up increases.
Val is an interesting guy. I don't quite understand him and now it looks like he might be heading for the sunset. Hopefully not.

Very good insights BourbanKing
I loved his early stuff but alas he morphed into a lazy, bullying jackass
I miss his heyday when he was great

He was quite a nightmare on the set of Island of Dr. Moreau, according to a number of interviews I've seen. Drove the original director off the project.

Val Kilmer's hostile behavior on the movie set of The Island Of Dr. Moreau was legendary. Then he and Marlon Brando (another difficult actor) developed a hatred for each other and the movie was in a shambles. A film that was supposed to take 6 weeks to shoot took 6 months, with people coming and going. Then it turned out to be a flop at the box office.

There are numerous accounts of him being one of the rudest celebrities out there. The icing on the cake was when he full on slapped an actress during a rehearsal. He shook her, threw her to the ground while Oliver Stone laughed. She filed a police report and was compensated by the studio.

https://jezebel.com/caitlin-oheaney-breaks-nda-to-publicly-allege-that-val-1819825864

Val Kilmer also got kicked off of the Batman franchise after only one movie for being a colossal dickhead. Joel Schumacher, the director told Val to stop being disrespectful to the crew and Val (instead of apologizing) refused to speak to him (or hid in his trailer) for the rest of the shoot. Val claimed that he wasn't brought back because he was he had booked another movie (The Saint) and nobody told him that they were fast-tracking the next Batman movie into production.

"...I was often unhappy trying to make pictures better..."

Well there's your problem!

If this guy thought he knew more about making pictures better than the director, writers, cinematographers, editors, and other professionals, no wonder he got a bad rap. Nobody likes a knowitall, or someone who tries to tell you how to do your job. Or who won't come out of his trailer if he doesnt get his way. Or who doesnt realize he's an asshole, and who thinks the real problem was financier ass.

Still, I won't hold anything he did on "Doctor Moreau" again him, apparently that set was such a nightmare that some people still think there was a real curse on the production.

To be fair, Steve Martin wrote in his book "Born Standing Up" that director John Frankenheimer stole his first true love when she went off to Europe to make a film that Frankenheimer was directing. Then, over 20 years later Frankenheimer tried to make a move on his then wife, Victoria Tennant.
I quote Steve Martin: "I've heard recently that John Franheimer has died, thou it was not I who killed him".

The new documentary "Val" (2021) has his own video taping of production on The Island of Dr. Moreau, with veteran director John Frankenheimer(hired to finish the film after the other director was fired, and evidently regretting his decision) telling Kilmer to "turn that video camera off" and Kilmer refusing to do so and stating his case why.

Its like a record of Kilmer's behavior. You can pick a side, but he sounds pretty jerky to me on it.