Drillers · Board game rules
When can I discard cards in Drillers?
Quick answer
You can discard cards during the Surfacing phase to gain 2 credits each, or keep unplayed cards in hand by paying 1 fuel per card during Upkeep. [p.10 — Discard Cards] [p.12 — Upkeep]
Details
During the Surfacing phase, if you end your Operations on the surface, you may discard any number of cards still in your hand. For each card you discard this way, you gain 2 credits. [p.10 — Discard Cards] This is optional and can be done as many times as you like.
During Upkeep, you must manage cards you want to keep between turns. You may keep 1 unplayed card in your hand for free. For each additional unplayed card you wish to save, you must pay 1 fuel during Upkeep. Any cards you don't keep are moved to your discard pile along with all cards from your play area. [p.12 — Upkeep]
Watch out: Discarding cards during Surfacing is different from the automatic discard during Upkeep. Cards discarded during Surfacing go away permanently (you gain credits for them), while cards in your play area are automatically discarded during Upkeep and go to your discard pile to be reshuffled later.