Krauser is attempting to duel with Leon. For Ada, she must stop the situation before she can retrieve the sample for Wesker.
This chapter is getting tougher with the entire army slashing you. Not all items are needed to be taken and there's nothing left to buy from the Merchant beside the crossbow. It's typically Resident Evil's signature weapon for Claire Redfield only.
This is the Asian release of Biohazard 4 or better known to all "Resident Evil 4" from 2006 that was ported entirely from the PlayStation 2 version but missing out lightning effects. This release and the Japanese release was distributed alone by Capcom without affliation from Ubisoft.
This bonus mission was better referred as "Separate Ways" to the fanbase.
Although this is an avoided PC port, it does have its own charms for it stability and modibility. Even on Windows 10, this ole house works with no complains at all.