Now that people have started to adapt to Stalkers, stealth doesnt seem to help much as I've been seen quite often while running hide+stealth. So you could drop stealth and get haste.
I'd put a rechg in placate if you intend to scrap a bit. Build Up+ET does a lot of damage on its own so you could drop a dmg in Energy Punch and AS to put another acc in tp foe and stun.
Other then that it seem ok.
personaly i'd do something like this as em/nin is quite end heavy and stun isn't really that good in PVP... the last 4 power are optional.
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Exported from Ver: 1.7.6.0 of the CoH_CoV Character Builder
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Name:
Level: 50
Archetype: Stalker
Primary: Energy Melee
Secondary: Ninjitsu
---------------------------------------------
01) --> Energy Punch==> Acc(1)Acc(3)Dmg(5)Dmg(15)Dmg(23)
01) --> Hide==> EndRdx(1)DefBuf(48)
02) --> Bone Smasher==> Acc(2)Acc(3)Dmg(5)Dmg(11)Dmg(23)EndRdx(40)
04) --> Ninja Reflexes==> EndRdx(4)DefBuf(19)DefBuf(19)DefBuf(25)EndRdx(46)
06) --> Assassin's Strike==> Acc(6)Acc(7)Dmg(7)Dmg(9)Dmg(9)Rechg(11)
08) --> Swift==> Run(8)
10) --> Teleport Foe==> Acc(10)Acc(50)
12) --> Placate==> Rechg(12)Rechg(13)Rechg(13)
14) --> Teleport==> EndRdx(14)EndRdx(15)
16) --> Kuji-In Rin==> Rechg(16)Rechg(17)Rechg(17)
18) --> Hurdle==> Jump(18)
20) --> Stamina==> EndMod(20)EndMod(21)EndMod(21)
22) --> Build Up==> Rechg(22)Rechg(50)Rechg(50)
24) --> Stealth==> EndRdx(24)EndRdx(25)
26) --> Energy Transfer==> Acc(26)Acc(27)Dmg(27)Dmg(31)Dmg(31)EndRdx(34)
28) --> Kuji-In Sha==> Rechg(28)Rechg(29)Rechg(29)Heal(37)Heal(37)Heal(37)
30) --> Invisibility==> EndRdx(30)EndRdx(31)
32) --> Total Focus==> Acc(32)Acc(33)Dmg(33)Dmg(33)EndRdx(34)EndRdx(34)
35) --> Danger Sense==> EndRdx(35)DefBuf(36)DefBuf(36)DefBuf(36)EndRdx(43)
38) --> Kuji-In Retsu==> Rechg(38)Rechg(39)Rechg(39)DefBuf(39)DefBuf(40)DefBuf(40)
41) --> Zapp==> Acc(41)Acc(42)Dmg(42)Dmg(42)Dmg(43)IntRdx(43)
44) --> Electric Shackles==> Acc(44)Acc(45)Hold(45)Hold(45)Hold(46)Rechg(46)
47) --> Hasten==> Rechg(47)Rechg(48)Rechg(48)
49) --> Super Speed==> EndRdx(49)
---------------------------------------------
01) --> Sprint==> Jump(1)
01) --> Brawl==> Acc(1)
01) --> Assassination==> Empty(1)
02) --> Rest==> Rechg(2)
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Defiant's GoEH/MILITIS METUS
This is the reaction on gins build having EM/nin myself
End reduce in hide...
Energy punch is okay
Bonesmasher is okay
Replace 1 acc in AS for recharge..using BU with it is godsent anyway
Build up I okay
Placate is your friend..3 slot it with recharge
Tp foe At least 2 acc...I got 2 acc 2 range myself but thats optional
2 end red 2 range in tp to be usefull as travel 2
3 recharge..you got for hit and run anyway 2 recharge perma's it
Swift is okay I guess
2 heal in health is enough..you manage okay with ku-jin sha
Stamina okay
Ku-jin sha can do 5 slotted but 6 is okay if you have the slots
Energy transfer is okay
Stealth slotting is okay
Stun is nice if you have fly for tp builds it sucks..unless you go pure tp foe?
Total Focus 3 damage 2 acc 1 end red...you might want 2 end reds but your screwed if you miss with this
2 Acc 2 To hit debuff in blinding powder
Retsu is okay
personaly I would replace some things
stun for hasten
tp for SS
In that case hurdle for health (your heal will safe you enough) (check your health after Energy transfer tho)
Fit ninja reflexes in, in sirens if you ever want to AS trou damage pbaoe
Stealth for Danger sense
Calltrops for blinding powder (1 slow will do..its not like you use it 20 times a minte)
tada:P
Build seems good but what about super jump an acrobatics?? Nin doesnt have resis knockback so i would go down the Super jump line maybe get hasten quite early an get SS later lvls for fun 
"We're not tools of the Government or anyone else...
Fighting was the only thing, the only thing I was good at...
But atleast...I always fought for what I believed in!" (Gray Fox)
@Captain Paragon EU @Captain Paragon.
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Exported from Ver: 1.7.6.0 of the CoH_CoV Character Builder
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Name:
Level: 41
Archetype: Stalker
Primary: Energy Melee
Secondary: Ninjitsu
---------------------------------------------
01) --> Energy Punch==> Dmg(1)Dmg(15)Acc(15)Acc(17)
01) --> Hide==> Empty(1)
02) --> Bone Smasher==> Dmg(2)Dmg(3)Dmg(3)Acc(13)Acc(13)
04) --> Danger Sense==> DefBuf(4)DefBuf(5)DefBuf(5)EndRdx(11)
06) --> Assassin's Strike==> Dmg(6)Dmg(7)Dmg(7)Acc(9)Acc(11)Acc(40)
08) --> Build Up==> Rechg(8)Rechg(9)Rechg(31)
10) --> Teleport Foe==> Acc(10)
12) --> Placate==>
14) --> Teleport==> EndRdx(14)
16) --> Kuji-In Rin==> Rechg(16)Rechg(17)Rechg(19)
18) --> Swift==> Run(18)Run(31)
20) --> Health==> Heal(20)Heal(21)Heal(21)
22) --> Stamina==> EndMod(22)EndMod(23)EndMod(23)
24) --> Kuji-In Sha==> Heal(24)Heal(25)Heal(25)Rechg(34)Rechg(34)Rechg(37)
26) --> Energy Transfer==> Dmg(26)Dmg(27)Dmg(27)Acc(29)Acc(29)Rechg(37)
28) --> Stealth==> EndRdx(28)
30) --> Stun==> Acc(30)
32) --> Total Focus==> Dmg(32)Dmg(33)Dmg(33)Acc(33)Acc(34)
35) --> Blinding Powder==> Acc(35)Acc(36)Rechg(36)Rechg(36)Rechg(37)
38) --> Kuji-In Retsu==> Rechg(38)Rechg(39)Rechg(39)DefBuf(39)DefBuf(40)DefBuf(40)
---------------------------------------------
01) --> Sprint==> EndRdx(1)Run(19)Run(31)
01) --> Brawl==> Empty(1)
02) --> Rest==> Empty(2)
01) --> Assassination==> Empty(1)
---------------------------------------------