JavaScript ES6
My answer assumes an only-ASCII encoding. This, I am sure, is the optimal solution for JavaScript ES6 in such a setting--this is the only encoding I wish to cover. If anyone wishes to tackle non-ASCII JS, be my guest ;) This clocks in at 61 bytes, leaving me 610 bytes to obfuscate.
n=>n=="C\u1d0f\u0274\u1d0f\u0280 O'B\u0280\u026a\u1d07\u0274"
Here is my obfuscated version, clocking in 588 bytes, less than 610.
(c,f,d,W=this,k=e=>+(`0x`+e),C=(O,...m)=>new(O[w=`constructor`]!=C[w]?O[w]:O)(...m))=>(($,_)=>$<=_&&_<=$)([g=W[(-~(Math.sqrt((P=parseInt)(P,b=31))+P(NaN,b+=5))+0xec)[D=`toString`](b)],t=n=>(j=n=>W[n[D](b)])(n),E=W[505019[D](b)]([...[1663483,552948,1629769,516801].map(e=>e[D](b)).join``].map((s,i)=>+(42742[D](2)[i])?s.toUpperCase():s).join``),A=n=>(p,c)=>p+n+c,...[for(x of c)x.charCodeAt()]].slice(-c.length),g(`[${[...`1${[...`mn0nkjp0mio0nkjp0mkg0ji0np0jp0mm0mkg0mho0nkjh0mio`].reduce(A(-~[]))}`.match(/../g).map(e=>""[w][E](P(e,b)-4)).reduce(a)].reduce((p,c)=>c<"!"?`${p},`:p+c)}]`))
Bonus material
This was my original, 947-byte obfuscation for the original challenge:
(c,d,f,M=Math,W=Z=this,q=($,_)=>$<=_&&_<=$,k=e=>+[`${+[+[]][+[]]}x`+e][+[]],
C=(O,...m)=>new(O[w=`constructor`]!=C[w]?O[w]:O)(...m))=>q([[d=[f=[~c]]+f],g
=W[(-~(M.sqrt(parseInt(P=parseInt,b=~-[[_=+!+[]<<-~![]][+[]]<<[_<<_/_][+[]]]
))+P(NaN,b+=5))+(e=>+[`${+[+[]][+[]]}x`+e][+[]])(C([],...C(Set,[..."abced"].
map(j=>j+i+(u+=[[u,u]],(i=j>i?j:i)?i:[]),i=u=[])[M.atan2(u[l="length"],~[]<<
~[])>>[]])).reduce(a=(p,c)=>p+c,[]+[]))|+[])[D=`toString`](b)],t=n=>(j=n=>W[
n[D](b)])(n),E=t(h=505019)([...[1663483,552948,1629769,h+=11782].map(e=>e[D]
(b)).reduce(a)].map((s,i)=>+[42742[D](2)][+[]][i]?s.toUpperCase():s).reduce(
a)),A=n=>(p,c)=>p+n+c,...[for(x of c)x[`c${E.slice(-7)}${[[]+[]][+[]][w][E](
P(42/_,_<<_<<_))+`${[]+[]}t`}`]()]].slice(-c[l]),g(`[${[...`1${[...`mn0nkjp`
+`0mio0nkjp0mkg0ji0np0jp0mm0mkg0mho0nkjh0mio`].reduce(A(-~[]))}`.match(/../g
).map(e=>[[]+[]][+[]][w][E](P(e,b)-4)).reduce(a)].reduce((p,c)=>c<"!"?`${p},
`:p+c)}]`))
