I am curious to how this can be done on hardcoe mode? I'm doing a frumentaris legion courier character, so that means no chem use. So stimpaks would be out. The last Legion character i completed i avoided Dead Money because of this, and didn't see a roleplay reason story wise to do it. I would like to try and complete all 4 DLCs in order for once though.

Survival and Blood sausages, and red paste.

Caravan Lunches can be crafted, and the ingredients are not that hard to find. There is plenty of Food, but the Radiation may be a problem due to a Player considering Rad-Away as a Drug/Chem. If a character has a high Survival Skill Dirty Water can be Mass Purified and then used for the HP regeneration.

A Role-Play reason to enter the Sierra Madre is investigating where a Legionaire dissapeared when patrolling.

U can get food from the vending machines. Sell ur stims and chems for caps at the traders and live high on the hog from dandy apples and whatnot.

Legion avoids chems on principle. But Stimpacks are a privilege, more-so if you are in a situation like Dead Money throws you in.

Also, you aren't born brainwashed into the Legion, nor are you some recruit. Even then, Frumantari operate under different codes. They are agents expected to infiltrate enemy lines, they aren't canon fodder. The "no stims" use is supposed to weed out the weak from the front-lines, and turn them into Veteran beasts. This does not extend to unique individuals.

Just steer clear of booze and narcotics. Use stims only if absolutely necessary.