HOW AND WHERE TO OBTAIN:The basic breakdown goes as follows:NBC Zombie -> Toxic Key -> Toxic Crate ->Oil Rig Keycard -> Oilrig Vault -> Temple/Arctica Keycard NBC Zombie: Can be located near gas zones - dressed in grey / yellow NBC Suits. Chance to drop Toxic Key.Make sure to wear NBC gear + a gas mask or you will fall to illness! And it's a pain to get rid of!A pro tip: Use a loud gun outside of the toxic gas to draw their attention - let them come to you! Toxic Crates: Found in toxic gas zones (NBC Gear will be required) and has a chance of the oilrig card.Use the key to open the crate, make sure to keep an eye on your filters durability! Oil Rig Keycard: Found in the toxic crate. It's small - so make sure to check the whole crate! It's not a guaranteed spawn - but you'll want to take it with you.Hint: These can be very valuable, as you can find access to the vault which could lead to top tier loot! Oil Rig Vault: Found on the Horizon Oil Rig in the Sea. Chance to find the Temple / Arctica keycards inside the vault! As well as up to .338 caliber weapons and of course, toxic gear / armour! VOTE BELOW:SHOULD WE ADD MORE KEYCARDS?Change ImageYes.. Duh..Change ImageNo.. There are more than enough!Change ImageInstructions weren't clear, I'm glued to the ceiling.