Classic Marathon: Marathon 100% Achievement Guide

Unmissable. In the 2nd mission of the game (Bigger Guns Nearby), you’ll get this after picking up the assault rifle.

This is a pretty complicated achievement to get, so i’ll link a video that helped show me the way. On mission 3 (never burn money) you can find a secret room hidden behind a wall in the dark corridor near the end of the level. You can tell which one has the door because theres a small pillar in front of it. if you enter there’ll be a ledge that you need to grenade climb up to get. There will be an invincibility powerup available to you so make sure you save it for when you start the climb. this is a pretty difficult achievement to get so you should save before entering (theres a save terminal in the elevator room nearby fortunately). you will likely need to reload your save a few times.

https://youtu.be/G3FvWnWbSuA?si=Qq-FlTfsH8FXbUa5&t=58

In mission 4 (defend THIS!) you’ll enter a room like this where the door behind you closes.

the exit is a behind a secret wall. but dont interact with it because if the exit is opened the achievement will be voided. instead, stay in the room and wait til you get crushed to death. if you die without opening the door the achievement will unlock

Driniols or Hulks are large creatures with a purple outfit that look like this (i got the image off google for clarity)

You can first find them in mission 6 (The Rose) at the beginning of the level. You dont need to punch them all the way until they die, so i recommend laying into them with some AR rounds and grenades first. as long as your final attack is a punch the achievement should unlock. i recommend loading a save and playing on kindergarten difficulty for this since the hulks do a lot of damage at close range.

Unmissable. On mission 9 (G4 Sunbathing) you will need to activate a satellite to send a message to earth. Once you do this you’ll get the achievement

Mission 14, Colony Ship for Sale, Cheap!, is the mission with the infamous switch puzzle in the middle of the room. The puzzle involves manually adjusting the heights of platforms until they are at a height where you can climb. It is quite a frustrating puzzle, but this information from the marathon spoiler guide helped me a lot. It shows how long you should let the pillars rise for before shutting them off.

Pillar 1 is the one closest to the entrance on the ground floor, and pillar 7 is closest to the exit high up in the wall.

It is important to note that YOU CANNOT TAKE ANY SPLASH DAMAGE FROM YOUR GRENADES during the level. make sure that if you do use them you are far away or not in a cramped space. a popular speedrun strat is to grenade climb without touching the puzzle at all but you need to complete it for the achievement.

On the 15th level (Habe Quiddam) there’s a section where you need to run through lava to pick up a device. if you stay in the lava and die you’ll get the achievement. not that this will unlock ONLY ON HABE QUIDDAM and not any of the other lava pools on the other levels.

Unmissable. At the start of the 17th mission in the game (Pfor Your Eyes Only…) you’ll be transported onto a pfor ship upon which you’ll get the achievement

Unmissable. On the 23rd mission (Pforaphobia) you will be forced to destory the spht controller before you can be transported out.

I recommend doing it on the 19th mission (unphorgiven) in this room with a large dropping point. in low gravity environments you can fly by aiming the flamethrower down and firing. You should have a full magazine when doing this. look down and shoot the flamethrower while you fall and you should fly. Press and release the fire button periodically so you dont empty your magazine too frequently and you should get it after 7 seconds. if youre having trouble, try going to the wall and aiming down while lining yourself against it.

Unmissable. complete the game on any difficulty and you should get this.

Same as the previous one, but you need to play through THE ENTIRE GAME on total carnage difficulty for this to unlock, not just the final level. if youre more familiar with the game before you can just run through on this level but i recommend doing another playthrough if you arent.

some tips

• use the marathon spoiler guide to find secret locations. total carnage removes your max ammo capacity so you should take all the ammo you find
• if you know the routes to the levels well, try not to kill enemies you dont need to, its easy to get overwhelmed especially in the early game when you dont have the firepower to deal with it. just run to the exit while taking as much ammo and fighting when necessary
• save and heal quickly and often. run back to all the save points and health stations because youll need it. you can easily lose a lot of progress by not saving because of how much damage the enemies do on this skill level.