Mass Effect 2
62 Achievements
1,355
55-70h
Big Game Hunter
Thresher Maw defeated
10
How to unlock the Big Game Hunter achievement in Mass Effect 2 - Definitive Guide
So, the Thresher Maw was a pretty intimidating enemy in the first game, randomly appearing on uncharted worlds; making short work of the Mako. Not anymore, though.
There is only one Thresher Maw and you shall be fighting it on foot. You will encounter it by doing Grunt's loyalty mission (note: If you do not release him from his tank, this achievement cannot be unlocked. I am unsure if releasing him after going through the Omega-4 Relay will still allow you to access his loyalty mission or not).
Fighting it on foot is pretty easy, depending on the difficulty you are playing on. You are given 5 minutes to "survive" it, but it should take less than half of that amount of time to kill it. It is you, Grunt, and one character of your choosing. It's health bar is strictly Armor (even on Insanity). The following weapons and skills will prove useful:
-Almost any heavy weapon, Heavy Pistols, Sniper Rifles, some Assault Rifles
-Incendiary Ammo (Vanguards, Soldiers, Grunt, Jacob)
-Warp (Adepts, Sentinels, Thane, Miranda)
-Inferno Grenade (Zaeed's loyalty power)
-Warp Ammo (Jack's loyalty power)
-Armor-Piercing Ammo (Garrus' loyalty power)
-Incinerate (Engineers, Infiltrators, Mordin)
-Reave (Samara's loyalty power)
The Thresher Maw doesn't require any super-crazy tactics. It will shoot the lovely acidic saliva at you causing a fair amount of damage to you. You can use the pillars littered throughout the battlefield for cover, but they can be destroyed by the Thresher Maw. It never gets close enough to attack you with melee strikes, but it will circle around the arena.
The fight isn't very difficult (especially on Normal or Casual), so this is an easy 10 gamerscore
I did this with Grunt and Morlin using nothing but assault rifles and submachine guns and it took me 4 minutes on Insanity.
You'll encounter a thresher maw during Grunt's loyalty mission. During Grunt's trial, one objective you'll have is to survive a thresher maw attack for five minutes. Use any heavy weapon that you have. I used the collector particle beam and took it down within a minute, but any heavy weapon will do the job. Remember, you are working on a timer here. If you don't kill the thresher maw within five minutes, you'll have to restart the game or reload your save. Make an extra save before beginning the trials.
This is missable. On the third part of Grunt’s loyalty mission, you’ll be asked to survive a thresher maw attack for 5 minutes. You must kill it within the timeframe to unlock the achievement. It only has an armor bar, so use heavy weapons and anti-armor powers.
The Thresher is a powerful and dangerous enemy especially on higher difficulties, but the strategy isn't too hard. The Thresher has a single Armor bar for both health and protection so ammo powers like Incendiary, Warp and Armor Piercing ammo are recommended if your Shepard or your other Squadmate has access to. Any other power that is effective against armor like incinerate, warp, reave and others also work very well in dealing large amounts of damage, any kind of Heavy Weapon can also quickly rack up damage as well.
Since Grunt is required for this mission, make sure he has incendiary ammo turned on, even though the power wheel will show it as ineffective, Concussive shot does stagger the Thresher and prevents it from launching as many acid barrages at once. Garrus Zaeed and Solider Shepard can use this strategy too if present to chain stagger the Thresher to help avoid damage.
Shooting the blue tendrils near the Threshers mouth deals significantly more damage than the rest of its body, but these tendrils are somewhat difficult to hit.
As long as you keep a good amount of pressure on the target you should defeat it with over a minute remaining even on Insanity difficulty.
This is missable. On the third part of Grunt’s loyalty mission, you’ll be asked to survive a thresher maw attack for 5 minutes. You must kill it within the timeframe to unlock the achievement. It only has an armor bar, so use heavy weapons and anti-armor powers.