Delta Green doesn’t get as much love as I think it deserves. This might be because Delta Green is Call of Cthulhu if it was somehow more depressing.
Something I don’t thing gets enough love willpower. Let’s work on that.
When you need to make a skill check, you can choose to before the roll roll a 1d2 and loose that much will power if able. You may do that up to two times. For each time you choose to lose willpower and do, you can increase your skill value by 1d10 for each time you choose to lose willpower.
You can choose to attempt to increase your skill value after a roll, but you must instead lose 1d4 willpower per 1d10 bonus to the skill value.
You must lose as much will power as you can. If you can not lose as willpower as the die indicated, you lost as much as you can and do not gain the benefit of the bonus to skill value. You may still not succeed at the skill check after you roll the extra dice.