Resource Attachments

Resource Attachments are one of the most vital type of cards in PURGE: Sins of Science. They produce the Energy that is required to play any cards or abilities. Currently, there are three "levels" of Resource Attachments, as every deck's resource attachments have the exact same Energy cost, TEK Requirement, and Energy output.

Low level
These are the Resource Attachments you play at the beginning of a game, as the others are still above your TEK level. "Low level" Resource Attachments have an Energy cost of 1, no TEK Requirement, and produce 2 Energy every turn.
 * Emergency Earth Coalition: Data Center
 * The Ancients: Dark Energy Dynamo
 * The Machine Horde: Slag Extractor

Mid level
Mid level Resource Attachments are generally played after you have played all of your low levels. This level of Resource Attachment has an Energy cost of 2, a TEK Requirement of 3, and produces 3 Energy each turn.
 * Emergency Earth Coalition: V-Sphere Holo Chamber
 * The Ancients: Background Radiation Collector
 * The Machine Horde: Mother Core

High level
Resource Attachments in the "high level" category are played late in a game due to their Energy cost of 4 and TEK Requirement of 6. They produce 4 Energy each turn.
 * Emergency Earth Coalition: Fusion Reactor
 * The Ancients: Solar Lines
 * The Machine Horde: Power Spire

Trivia

 * The Inaugural (Kickstarter) Edition misprinted Fusion Reactor's Energy production as 6, instead of the usual 4.