Nearly every attachment in Resident Evil 4 Remake has a purpose and can completely change how a weapon feels to use. The Red9 Stock is a prime example of this, changing the old-school handgun from a rather okay weapon into the beast that it was meant to be. As far as rifle attachments go, one attachment is almost completely useless outside of one niche which makes it a requirement. Here is how to get and use the Biosensor Scope in Resident Evil 4 Remake.
Where to Find the Thermal Scope in Resident Evil 4 Remake
The Biosensor Scope is found when exploring the labs later on in the game, after you have encountered some of the first Regenerator enemies and been forced to run away. As you reach the other side of the Incubation Labs, where the Regenerators are housed in the test tubes, you will find the Biosensor Scope inside a small case. Its description says it is a scope that “highlights biological entities” and can be mounted to both automatic and semi-automatic rifles. This includes the LE 5 (which you recently acquired) and the TMP alongside all rifle weapons.
While that does not sound very helpful, it is the only way you can kill the Regenerator enemy. It is necessary if you want to get the Wrench and progress through the game, as a Regenerator in one of the test tubes has it. To kill a Regenerator with it, aim your weapon at it and search for the three glowing hearts in its chest. Shoot each of them until they pop, and the Regenerator will do one of two things. It will either lose its torso and die, or it will become an Iron Maiden. If the latter occurs, use the Biosensor Scope to spot its glowing head and shoot it. Just be careful of the millions of spikes it now has in its body that can be sent out.
Related: How Many Chapters Are in Resident Evil 4 Remake?
While it only has a niche use case, being able to kill a Regenerator is invaluable for later stages of the game. If you want more details regarding the Wrench we just mentioned, check out our guide on the subject.