Revealing mistake: When Damoscinos is dying, just after being bitten, he stumbles to the ground. As he does so, you can see the tube feeding the green "blood" to his neck on the ground behind him.
Revealing mistake: In the opening scene, Novak attacks and bites a woman, and when the security guard begins to shoot at Novak there are bumps on Novak's back exactly where he gets shot, signifying the explosive squibs. (00:02:50)
Revealing mistake: This is during the fight between Blade and Nomak at the House of Pain. While Blade is walking across the wooden platform, you can see Nomak readying himself to get launched on the platform. (00:52:20)
Revealing mistake: When Blade slices Reinhardt in half, as the sunglasses fly off the two halves of his face you can briefly see that Reinhardt (or more precisely the CGI model of him) has no eyes. (01:37:23)
Revealing mistake: Near the end, when Blade pierces Lomac's heart with the sword and blood comes out of his mouth, he starts wobbling around and they do a wide shot, behind Lomac you can see the tube that feeds the blood on the ground and it comes up under his costume.
Chosen answer: Killing Scud with it probably was more satisfying for Blade than Reinhardt, who he easily beat as well. He hates familiars and that moment he used the bomb to have Scud reveal his betrayal, and then kill him, so he won't get away. Reinhardt he knew would not try to run, he was killing him anyway.
lionhead
Agreed. I saw it as he was waiting for Scud to show his hand. Like Blade said, he knew Scud was a traitor/a familiar the moment they turned him. He was waiting for the perfect time to let Scud know that he was already well informed on his betrayal, and that his azz was now cooked. Doing it that way was way more satisfying for Blade.