itch.io

Enemies that are carrying key cards will have a little sparkle usually near their hip, but this only shows while they're in their idle or patrolling state - it will not show if they are searching or chasing.

There is a missile mech in level 1 near the purple control pannel that has a tier 1 card, and an executive in level 3 that has a tier 2 card. That executive is somewhere behind door #4, and is also the only executive in that area.