Nitpicks
1. When Stryker is in the old castle just before the dogs attack him, a snake creeps up to him, a snake which appears to be a python or boa constrictor. Yet, the castle in in Europe (Spain or France) and pythons and boa constrictors are not native to Europe.
2. When Stryker jumps down the shaft when the dogs chase him before he lands in that creepy room with the skeletons, armor, and weapons where he finds the key, the shaft he falls down looks futuristic and looks like it could belong in some spaceship from Star Wars or Star Trek, not a medieval castle.