Unreal Tournament 3

Set up a match using the Berserker Mutator this way u will get 15 rounds in your Anvril.. Play in VCTF to 1 capture on the map Rails & 60 mins to give u unlimited time to get your kills, as soon as you spawn there will be a Anvril lying on the ground on the road, simply get 15 kills with this weapon using the RT not the alternate LT & as soon as you get the "Big game hunter" go grab the flag & capture it..
Repeat this 9 more times for the achievement
(Can be done using bots which is quicker but a little frustrating at times or play a friend & camp at there spawn or u could just use another controller which would take the longest imo.)

Need any help on any other Achievements..
Hit me up:: KRUCIAL III. ;)

I found the fastest way for me was to have another profile (Local, Silver or Gold) signed onto a second controller and to choose:

Instant Action
Warfare
Sinkhole
Splitscreen:Yes
Contestants:2
Score:1
Time:5-10 depending on your preference
Then hit (X) to open the mutators menu
Clear any you might have enabled then activate (using Y) Super Berserk

The Anvril Launcher is on the upper level on either side after you grab your orb and leave your base. You will have 15 shots so assuming you don't miss you can just run 10 games per person wanting the achievement, The other player will spawn upstairs above their core in either room - generally the one across from where you are. Just walk through the node on your way to the other player... by the time you finish killing him 15 times the node will be yours. Once you have the award simply destroy the core and repeat until the achievement pops.

For this achievement you need to attain the "Big Game Hunter" award in 10 different matches. Below is the easiest way of going about doing this.

First of all you'll need 2 controllers for this method. Sign the second controller in as a Xbox Live guest. From there go into multiplayer, create a player match and choose these settings:

Player Match
Minimum Players: 2
Private Slots: 2
Mode: Vehicle Capture The Flag
Map: Rails
Splitscreen: Yes
Bots: Disabled
Goal Score: 1
Time Limit: 20 minutes

Now press "X" to bring up the mutators menu, from here you'll want to select the "Super Berserk" mutation and add it by pressing "Y".

Now you're ready to start the game up and work on this achievement. When the match loads up you'll first of all want to grab the AVRiL which can be found just outside of your spawn area on the circular road. Once you've picked it up you need to travel across the map and find a place to spawn kill, I suggest standing on or close to the ramp next to the AVRiL outside of the enemy base as it's possible the most centralised point. Now use your second controller to run the guest account up to you and repeatedly kill it. When firing the AVRiL be sure to use it's primary fire by using the "RT", do not pull "LT".

Continue killing the guest account and upon the 15th kill the commentator will say; "Big Game Hunter". At this point stop killing the guest account, grab the enemy flag and return to your base to end the match. Once the match has ended let it load up the match again and repeat the process, do this 10 times in total and the achievement will unlock.

Lastly I have 2 additional tips, use the hoverboard to get around the map, press "X" to jump on or off your board. Doing this will enable you to travel across the map significantly faster. If for whatever reason you miss a shot, you won't have enough ammo on you to reach the 15 kills needed for the award and so have your guest account pick up the AVRiL and switch to it as it's current weapon, upon killing the guest you'll be able to pick up it's dropped AVRiL and your ammo will be replenished.

I got tired of trying this on vehicles since the Goliath takes 3 shots and the Scorpion shoots down your missiles and the Manta ducks behind cover and the missile misses so I ... um, ran up to bots and shot them directly with the missile. So the important point here is that you don't have to kill a vehicle, you just have to kill a character. Signing in another player works, but also if you go to an enemy base, the bots guarding the flag don't move until you get close so you can actually shoot them with the missile from some distance away.

Start up a VCTF game on rails with a second controller. Head to the other base and walk your second controller to yourself 15 times, killing him with your Anvril each time. One done, start a new match and repeat. This is one of the longer weapon achievements but still not much skill requried

After reading all the solutions I wanted to Speed this up.
It CAN be done in Instant Action.
Mode: Instant actions / VCTF
Map: Necropolis
Bots Skill :Novice
# 16
Goal score:0
Time: 60
Force Respawn: Yes

Now the twist
Mutators
1.) Super Berserk
2.) Weapon Replacement: Everything for the Impact Hammer

The Strategy.
Once you spawn, snagged the Anvril from behind your flag.
Hop on your board and zip over to the blue flag, snag it than wait just inside the building.
The flag will be the beacon, so they will charger you with the impact hammer.
Just pick them off as they come at you.
IF you run low on ammo becuase you missed, just charge an enemy and pull the trigger killing yourself in the process.
Once you respawn at your base, grab the anvil and hover back over.

I was able to get 15 kills with it doing this method in about 3-5 minutes vs all the other Guides.

Once you get the big game hunter, go back to main screen, and reload. All your setting will be saved.