The Outer Worlds: Spacer's Choice Edition

This achievement is unlocked when you start and complete the game on Supernova difficulty. The game does not allow you to lower the difficulty for an interval and resume supernova play. Thus, to earn this achievement, you must commit to it before you start a new game.

It is the most challenging game mode. You can only make hard, manual saves on your ship although the game creates auto-saves periodically. Enemies are more powerful and robust than the player-character. If you don’t eat, drink, and sleep; your performance suffers and, taken to the extreme, you die. Unlike other modes, companions do not resurrect when killed but are permanently lost.

Nevertheless, this is not a souls-type game where you have to die often in order to acquire the wherewithal to persevere. The most intimidating aspect of the supernova mode is its grandiose-sounding name. With the right build, once you’ve acquired some decent weapons in the first hour of play, you should be high enough on the learning curve to proceed through the game without undue hindrance.

Because you commit to this achievement at the start of the game, your decisions are very important. Assuming you want to complete all (or most) of the achievements in the game, there are three main strategies to consider. Each main strategy, as is to be expected, is subject to individual variations:

• One playthrough with substantial mop-up on story mode: This is the most efficient approach but the least immersive. You start and finish the game on supernova doing the bare minimum of main story quests to get you to the end and pop this achievement along with an achievement for finishing the game while playing on hard. You take a very abbreviated approach—avoiding combat to the maximum extent and relying on skill checks to advance the story. The game creates a special save file at the point of no return—one that can’t be overwritten. After finishing the game, load up this save file. Change the difficulty from supernova to story. Mop up all remaining achievements. It ensures all gameplay is relevant during a single playthrough while falling back to story mode for the predominance of play once supernova pops.
• Two playthroughs. This is the second most efficient approach but, while more immersive than the preceding, does NOT provide the optimal immersive experience. There are two variants to this approach.

1. A comprehensive first play-through on story mode where most of the achievements are unlocked. Using some save manipulation for mutually exclusive achievements, it is possible to unlock all achievements but two—this achievement for playing on supernova and the achievement for playing on hard difficulty. Afterwards, start a new game on supernova. Finish the game using an abbreviated speedrun approach to pop the final two achievements including this one.
2. Two playthroughs without save manipulation. The first playthrough is the more thorough one on story mode to unlock most of the achievements. During this playthrough, unlock the Monarch Abides and Ludwig was Right achievements—these achievements require combat and have mutually exclusive counterparts that are resolved without combat. A second, supernova playthrough will unlock Peace in our Time and Mightier than the Sword. The latter achievement requires decisions early in the game as prerequisites—sided with Spacer’s Choice with power to Edgewater, persuade deserters to return, & place Reed in charge. Finish the game unlocking this supernova achievement and the one for finishing the game on hard.

• One comprehensive playthrough on supernova to unlock ALL achievements. This is the least efficient from an achievement hunting standpoint but the most rewarding in terms of immersive experience. It requires some save manipulation to get the mutually exclusive achievements discussed above. In order to minimize risk and expedite game play, I recommend the following:

1. Character build: Below average strength & temperament, good dexterity & charm, very high intelligence & perception while putting the first two points in ranged weapons and stealth. This creates a super stealthy sniper who sneaks by enemies when possible and kills from very far range when combat is required. The intent is to expose the character to near zero damage removing the risk of playing on supernova.
2. Weapons: Except for specific weapon related achievements, only two types of weapons are employed. A sniper-type rifle and an assault-type rifle. As the game progresses, more capable variants of these two weapon types become available. The first sniper-type rifle is obtained within the first half hour of play by looting Bertie Cotton’s body during the Fistful of Digits side quest given by Constable Reyes in Edgewater. Assault rifles are found as common loot—again, within the first half hour of play. The sniper-type rifle is initially outfitted with a Mag-2-Power mod for plasma damage and then later with a Mag-2-Melt for corrosive damage. The assault rifle will always be outfitted with the Mag-2-Zap mod for shock damage. The primary weapon is the long-range weapon. The assault rifle is a fail-safe in case enemies approach. The shock damage has a paralytic effect that causes approaching enemies to spaz out.
3. Armor & Helmets: Since damage is avoided, the main purpose of armor and helmets is to provide skill bonuses. As soon as tier 3 perks become available, get the armor master perk to double armor and helmet bonuses.
4. Skill Progression: After getting the ranged weapons, stealth, and dialog skill trees to 40; pump science to 100. Science substantially magnifies the environmental damage we are using—plasma, corrosive, & shock. Additionally, a science skill of 100 reduces tinkering (weapon upgrade) costs by 90% ensuring your weaponry is always the maximum-allowed 5 levels higher than the player-character’s.
5. Companions: Avoid taking them whenever possible. Get the tier 1 perk, lone wolf, soonest to give you a skills boost when traveling without companions. When companions are required, set their proclivities to far, ranged, and passive. Always direct them to position themselves in a safe spot. Since inspiration is below 20, we do not have access to special abilities. To unlock Got your Back for killing 50 enemies with special abilities, save enough skill points to bring inspiration to 20. Then, on a throw-away save file, unlock the achievement. Afterwards, load up your save file of record and apply the saved skill points where they will do the most good. This guide explains how to get the Got your Back achievement on a throw-away file: Solution for Got Your Back In The Outer Worlds: Spacer's Choice Edition
6. Flaws: Get the Flawed Hero achievement on a throw-away file and, otherwise, refuse all flaws. The last thing you need on a supernova playthrough is the inconvenience of flaws. This guide explains how to get the flaw-related achievement on a throwaway file: Solution for Flawed Hero In The Outer Worlds: Spacer's Choice Edition

Using the above approach, you will have acclimated yourself to supernova play in the first hour and mastered it by the second hour. You might sustain some damage as you’re working your way up the learning curve. However, once you’ve internalized the process, you should quickly find yourself in zero damage incurred mode. You’ll find the major drawback of playing on supernova is not risk but the inconvenience of sleeping, eating, and drinking. You must also baby your companions to avoid getting them permanently killed but note that they can be very useful outside of combat—providing bonuses in order to pass skill checks.

When you get to the game’s final confrontation, you have three options.

1. Use dialog skills to avoid fighting the boss-type enemy
2. Hack the terminal to get the automechanicals to fight one another for an easy mop-up afterwards
3. Fight the boss-type enemy toe to toe—it’s only challenging when confronted at a low level and you will be well above 30—probably in the 40s—at this point.

Following the final encounter, whether you resort to diplomacy or combat, you will meet with Phineas. After a short dialog, the achievement unlocks. The following video shows the final sequence after the game’s point of no return. It is a non-combat approach and, thus, is applicable to all 3 strategies outlined above:
Note that the player-character in the above video is at level 51 having done every task & quest (main, side, & faction) available in the game and explored every nook & cranny. He does not need to resort to diplomacy over combat and is more than capable of taking the final boss level enemy to the woodshed.