In 1.5, the clothing that Leon Scott Kennedy and Elza Walker wear have a functional purpose in gameplay. Each "costume" has a set defense value and unique attributes, such as functionality for the Combat Knife or extra item slots via a Side Pack. They are able to wear three different sets of equipment:
- Standard: Leon wears his R.P.D. uniform and Elza wears her racing suit. Leon already has a knife sheath, while Elza has nothing.
- R.P.D. armor: At the Raccoon City Police Department, Leon and Elza are able to find a tactical vest and Side Pack belonging to the police force. In addition to the armor, Elza also receives a sheath for the Combat Knife.
- U.S.S. armor: At the Raccoon City Underground Laboratory, Leon and Elza obtain a set of tactical armor and a Side Pack belonging to the Umbrella Security Service. In addition to the armor, Elza also receives a sheath for the Combat Knife.
When the character is attacked by enemies and receives damage, the clothing and equipment will begin to show visible signs of damage as well. Damaged and broken equipment loses defense, leaving the player vulnerable. Once damage has appeared on the characters, it cannot be repaired.
The Costume Change System was created to implement new RPG elements into the game. The system may have been planned to include more in-depth costume options, such as making the decision to choose between a jacket (which would offer higher defense and more item slots via extra pockets) or a shirt (which essentially had no advantage). These choices would have had a deeper effect on the player's psyche, shaping how they play the game. Both the July and August 1996 builds of 1.5 feature Leon in his civilian clothes. It is likely that these builds had planned to incorporate his clothing into the system.
In the November 1996 build, the "Standard", "R.P.D. armor", and "U.S.S. armor" models have all been created. They also feature full damage textures. However, not all of the textures are mapped properly. Leon and Claire can trigger one of the damage stages in-game by taking enough damage, but they cannot upgrade costumes. There does not appear to be a change in defense after taking damage.
The textures are mapped in sections, suggesting there may have been a way to only show signs of damage on certain parts of the costumes. This would mean that the damage accumulated from the "Standard" costume would not be repaired on the "R.P.D. armor" costume, leaving only the R.P.D. equipment in good shape.
Had the game incorporated alternate costumes, they may have been affected by this system as well.
This system appears in later games. The retail version of Resident Evil 2 implements an upgrade system by giving the player the chance to equip a Side Pack in the R.P.D.'s armory, which adds it to Leon and Claire's costume. Later in the game, Leon, Claire, and Sherry receive changes to their costumes that only affect the story, not gameplay. Resident Evil 3: Nemesis continues this same trend by upgrading Jill's costume with the Side Pack. The system was not fully implemented until Resident Evil 4, where Leon is able to equip tactical armor which affects his defense stats and changes his appearance.