Complete the following achievements to unlock Microsoft Gamerscore points.

Achievement	How to unlock	Points
All Kleer	Kill fifty healthy Kleers with a direct double shotgun hit.	20
All Roads Lead To Rome	Head into Rome. Ditch Rodriguez.	10
Are You Not Entertained?	Party like it's 199.	10
Atomic Wedgie	Use the mininuke to eliminate hundred enemies at once.	50
Brass Lantern	Finish a text adventure. On an oil rig. During an alien invasion.	15
Bullseye	One-shot kill three Werebulls with a shotgun.	20
Class Reunion	Navigate the citadel of Carcassonne. Start reassembling your team.	10
Classic Hero Stuff	Save a princess. Doesn't get more classic than that.	15
Cultist Stimulator	Recover a key stolen by a cultist.	15
Dismemberfest	Dismember fifty enemies with cannonballs.	20
Ecclesiastical Extraction	Save the rookie. Find Father Mikhail. See the sights.	10
Enemy of My Enemy	Make twenty enemies kill each other using Psychotropic Grenades.	20
For the Cause	Find out what happened to Alessandro.	15
From Earth With Love	Send Mental a message he won't forget.	10
Fulbert le Fou	Discover Fulbert's great invention.	15
Get Serious	Unlock 10 S.A.M.s in a single playthrough.	20
Hard Science Fiction	Get a weaponized black hole, using science.	15
Harvest Festival	Harvest hundred enemies with a combine harvester.	20
Harvest Noon	Don't fear the reaper. Be the reaper.	10
Heads Up!	Kill hundred enemies with a headshot.	20
Holy Driver	Ride the Popemobile to victory.	10
Hot Hot Hot	Run away from an angry volcano you foolishly antagonized.	10
La Nonna e Mobile	Meet a powerful granny.	10
Max Pain	Kill five enemies during a single Time Warp slowdown.	20
Megabarf	Kill a Belcher using Belcher collateral barf damage.	20
Mushroom Surprise	Find out what happened to the English airman.	15
No Surrender	Kill five enemies in a row while your health is below 10 HP.	20
Oh, Shut Up	Destroy ten propaganda drones.	20
Oil's Well That Ends Well	Escape the Oil Rig.	10
Pow Pow!	Kill an Aludran Reptiloid using nothing but a pistol.	20
Quadruple the Gun	Kill twenty enemies while dual wielding double shotguns.	20
Quality Time	Go on a date with Hellfire.	15
Regression	Get knocked on the head and remember how you got here.	5
Roman Holiday	Get together with your friends and kill something big.	10
Say Hello To My Mini Friend	Spend thousand minigun rounds while firing continuously.	50
See Carcassonne And Die	Cross the French countryside and get very cross.	10
Serious Art	Protect humanity's treasures from invaders with no taste.	15
Serious Sam	Beat the game on any difficulty.	100
Signature Move	Sign Secchi's rifle.	15
Southern Gentleman	Assist a couple of young ladies out hunting.	15
Spinal Tap	Kill eleven different enemies using melee attacks.	20
Spread the Joy	Kill three enemies with a double shotgun blast.	20
Tear 'n' Rip	Melee a big enemy.	50
That Belongs In A Museum	Recover the alien artifact located by Dr. Stein.	15
That Burning Sensation	Collect scorched aliens for Professor Kiesel.	15
The French Achievement	Achievement is your middle name.	15
The Informant?	What if you could talk to the monsters?	10
The Last Human	Get justice. Get the Holy Grail. Get screwed over.	10
The Spirit of Roma	Fight alongside Massimo Murena.	15
This Seems Safe	Unlock a S.A.M.	20
Veni Vidi Witchy	Kill a Witchbride using C4.	20
Volcano Antagonizer	Die HAARP With A Vengeance.	10
Where's That Girl	Make sure Gabriella is OK.	15
You Have Been Wormed	Assist Dr. Vermetti in his war on worms.	15