I've been trying to get Berserker Diamond for a while, off and on, alternating between different character classes to see what works best. A while ago, I concluded that Scout is the weakest melee class. Marine can dish it out, but not take it, thanks to Rip and Tear trait, and the Technician can take it, but not dish it out, thanks to Blademaster and Juggernaught traits, but the Scout just had to rely on being sneaky, which means you're screwed if you get caught without energy... that is until the Executioner trait was added in this version, which turns things around and puts the Scout on top, since now he can dish it out and avoid taking it. :)
I went with a Ghost build, which meant that I had to waste a level getting Eagle Eye, but it was totally worth it, especially when combined with the utility amp I found that gave me extra energy from crates, and when combined with Energy Leech 2, I always had tons of energy for going stealthy-stealth everywhere and critting every enemy I came across. Very few enemies didn't get gibbed, which is why my kill ratio was so high. :) (The only enemies left alive were from early levels)
I only went up to Ghost 2 for the reduced energy usage; getting Ghost 3 seemed pointless, since Ghost already (apparently) has the undocumented feature of acting like Bloodhound trait. Once you detect an enemy by going within 7 squares of it, you continue detecting it forever, no matter how far away you are. If it dies, you can even detect the Nightmare difficulty purple square that shows where it's going to respawn, and you can detect the respawned exalted version. This isn't how I expected Ghost trait to behave from the description; I thought that you only detect enemies within 7 squares, and if they go beyond that, you can't detect them any more. So I'm not sure if this behaviour is a bug or feature.
I spent a good chunk of the run with a machete with Vampyric 2 on it, which I found in Valhalla Command. (Valhalla Command was kind of harrowing; I dealt with the Guardian Bots with an EMP grenade and some well placed stealth strikes) Later, I replaced that with a katana with Vampyric 3, and finally the Demonic Sword, which has Vampyric 5. (What can I say? I've always been fond of the Vampyre trait) :D By the end, I was so strong that I was throwing away med kits, something I almost never do in this game, especially a melee game, where you expect to take more damage.
All that said, as much fun as this was, I have a feeling the Scout is a little OP in melee now. It was underpowered before, but it looks like the devteam went too far in the other direction. :)
Tormuse, level 16 Scout, defeated
The Summoner against all odds.
He survived for 12166 turns.
The run time was 5h 38m 10s.
He scored 8872 points.
He opposed the NIGHTMARE!
He was an Angel of Berserk!
CALLISTO L2 -> Valhalla Terminal L1
Valhalla Terminal L2 - Lockdown
Valhalla Terminal L3 -> Valhalla Command
Valhalla Command - cleared
EUROPA L2 - Volatile Storage
EUROPA L2 -> Conamara Chaos Biolabs L1
Conamara Chaos Biolabs L1 - Infestation
Conamara Chaos Biolabs L2 -> Containment Area
Containment Area - cleared
IO L3 -> Io Black Site L1
Io Black Site L2 -> Black Site Vaults
Black Site Vaults - cleared
The Shattered Abyss - cleared
BEYOND L2 - Exalted Curse
BEYOND L2 -> Limbo
Limbo - cleared
Awards
CRI Star (bronze cluster) (+25)
* 25+ kills without taking damage
CRI Star (silver cluster) (+50)
* 50+ kills without taking damage
Explorer Ribbon (+50)
* Visited all encountered special levels
Conqueror Ribbon (+100)
* Completed all encountered special levels
Berserker Bronze Badge
* Reach Io on Angel of Berserk
Berserker Silver Badge
* Complete Angel of Berserk (AoB)
Berserker Gold Badge
* Complete AoB on Hard
Berserker Platinum Badge
* Complete AoB on Nightmare!
Berserker Diamond Badge
* Complete AoB on N! with 80%+ kills
He killed 611 out of 632 enemies.
51 archreavers
49 fiends
26 exalted ravagers
16 plasma ravagers
21 exalted fiends
23 rocket turrets
37 turrets
1 Summoner
2 military sentrys
8 security sentrys
4 former CRI grunts
30 CalSec bots
25 exalted reavers
3 former CRI soldiers
16 exalted kerbeross
4 corrupted sergeants
41 ravagers
6 combat drones
12 former soldiers
5 former guards
3 former heavys
21 fire fiends
8 siege ravagers
7 former sergeants
27 exalted soldiers
8 cryobeross
1 corrupted heavy
13 CRI marines
4 guardian bots
2 hellish soldiers
5 military drones
2 former CRI commandos
4 former grunts
8 toxic reavers
18 ice fiends
1 Swordmaster
1 former CRI sergeant
20 armored ravagers
14 CRI bots
71 reavers
4 corrupted commandos
7 cybeross
12 security drones
21 cryoreavers
6 kerbeross
4 former commandos
13 CalSec sentrys
1 toxiberos
Traits
Skilled L2
Hellrunner L2
Juggler
Dash
Eagle Eye
Executioner L2
Energy leech L2
Dodgemaster
Second Wind
GHOST L2
Trait order
Exe->Exe->Skl->EnL->Skl->EE->MGH->EnL->
MGH->Das->Hr->Hr->Dm->Jug->SWd
Equipment
Slot #1 : demonic sword
* Frenzy 10
* Vampiric 5
Slot #2 : chainsaw
Body : ENV armor PA
* Swift
* Powered
* Sealed
* Fireproof
* Heated
Head : marine helmet PB
* Durable
* Critical 25
Utility : AV2 utility AMP
* Energetic
* Aim assist
Inventory
plasma grenade (x1)
gas grenade (x2)
EMP grenade (x3)
krak grenade (x3)
krak grenade (x3)
CRI phase kit (x1)
multitool (x4)
stimpack (x3)
stimpack (x1)
small medkit (x1)
large medkit
large medkit
P.S. I considered putting "Silent, but deadly" as the post title, but decided I preferred the Starcraft Ghost reference. :)