Raid Mechanic ideas
Hot Potato - Object Rolls own initiative on spawn. If result places it within the next 3 turns, roll again until its initiative is beyond the next three turns. Once it reaches its turn, it explodes.
Nuclear Cores - Hot Potato-Lite. Players adds 1 to a "Radiation" counter if they are holding or within 10ft. of a nuclear core at the start of their turn. Once the Radiation counter reaches 3, the player's hitpoints are instantly reduced to 0.
Keyholder - Think Operator/Scanner/Suppressor. An object you can pick up. While holding the object, you can interact with specific things.
Symbols - When certain criteria is met, a symbol will appear that can only be seen by the one(s) who met said criteria. Symbol identification must be shared.
Plates - Control the zone. If one or more players remains within the plate area at the end of their turn, the plate is primed. If the player remains within the plate on the next turn, the plate is activated and remains active until another mechanic disables them. If an enemy creature ends their turn on a plate without a player also inhabiting the plate area, the plate is disabled.