diff --git a/dist/lodash.compat.js b/dist/lodash.compat.js
index 23798ba85..c2750e42c 100644
--- a/dist/lodash.compat.js
+++ b/dist/lodash.compat.js
@@ -1786,7 +1786,7 @@
 
     /**
      * Gets the appropriate "indexOf" function. If the `_.indexOf` method is
-     * customized, this method returns the custom method, otherwise it returns
+     * customized this method returns the custom method, otherwise it returns
      * the `baseIndexOf` function.
      *
      * @private
@@ -5394,9 +5394,10 @@
     }
 
     /**
-     * Creates an array of grouped elements, the first of which contains the first
-     * elements of the given arrays, the second of which contains the second
-     * elements of the given arrays, and so on.
+     * Creates an array of grouped elements, the first of which contains the
+     * first elements of the given arrays, the second of which contains the second
+     * elements of the given arrays, and so on. If a zipped value is provided its
+     * corresponding unzipped value will be returned.
      *
      * @static
      * @memberOf _
@@ -5408,6 +5409,9 @@
      *
      * _.zip(['fred', 'barney'], [30, 40], [true, false]);
      * // => [['fred', 30, true], ['barney', 40, false]]
+     *
+     * _.unzip([['fred', 30, true], ['barney', 40, false]]);
+     * // => [['fred', 'barney'], [30, 40], [true, false]]
      */
     function zip() {
       var array = arguments.length > 1 ? arguments : arguments[0],
@@ -6950,7 +6954,7 @@
     lodash.unzip = zip;
 
     // add functions to `lodash.prototype`
-    mixin(lodash);
+    mixin(assign({}, lodash));
 
     /*--------------------------------------------------------------------------*/
 
diff --git a/dist/lodash.compat.min.js b/dist/lodash.compat.min.js
index d03b6ba6b..4d948bc04 100644
--- a/dist/lodash.compat.min.js
+++ b/dist/lodash.compat.min.js
@@ -46,12 +46,12 @@ if(typeof t!="number"&&null!=t){var o=u;for(t=v.createCallback(t,e,3);o--&&t(n[o
 return n},v.range=function(n,t,e){n=+n||0,e=typeof e=="number"?e:+e||1,null==t&&(t=n,n=0);var r=-1;t=Be(0,ye((t-n)/(e||1)));for(var u=Zt(t);++r<t;)u[r]=n,n+=e;return u},v.reject=function(n,t,e){return t=v.createCallback(t,e,3),At(n,function(n,e,r){return!t(n,e,r)})},v.remove=function(n,t,e){var r=-1,u=n?n.length:0,o=[];for(t=v.createCallback(t,e,3);++r<u;)e=n[r],t(e,r,n)&&(o.push(e),ke.call(n,r--,1),u--);return o},v.rest=qt,v.shuffle=Tt,v.sortBy=function(n,t,e){var r=-1,o=qe(t),a=n?n.length:0,f=Zt(typeof a=="number"?a:0);
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-},v.every=St,v.find=It,v.findIndex=function(n,t,e){var r=-1,u=n?n.length:0;for(t=v.createCallback(t,e,3);++r<u;)if(t(n[r],r,n))return r;return-1},v.findKey=function(n,t,e){var r;return t=v.createCallback(t,e,3),tr(n,function(n,e,u){return t(n,e,u)?(r=e,false):void 0}),r},v.findLast=function(n,t,e){var r;return t=v.createCallback(t,e,3),Nt(n,function(n,e,u){return t(n,e,u)?(r=n,false):void 0}),r},v.findLastIndex=function(n,t,e){var r=n?n.length:0;for(t=v.createCallback(t,e,3);r--;)if(t(n[r],r,n))return r;
-return-1},v.findLastKey=function(n,t,e){var r;return t=v.createCallback(t,e,3),bt(n,function(n,e,u){return t(n,e,u)?(r=e,false):void 0}),r},v.has=function(n,t){return n?we.call(n,t):false},v.identity=Ht,v.indexOf=zt,v.isArguments=dt,v.isArray=qe,v.isBoolean=function(n){return true===n||false===n||n&&typeof n=="object"&&he.call(n)==L||false},v.isDate=function(n){return n&&typeof n=="object"&&he.call(n)==z||false},v.isElement=function(n){return n&&1===n.nodeType||false},v.isEmpty=function(n){var t=true;if(!n)return t;var e=he.call(n),r=n.length;
-return e==$||e==M||(Le.argsClass?e==T:dt(n))||e==G&&typeof r=="number"&&jt(n.splice)?!r:(tr(n,function(){return t=false}),t)},v.isEqual=function(n,t,e,r){return at(n,t,typeof e=="function"&&tt(e,r,2))},v.isFinite=function(n){return Ie(n)&&!De(parseFloat(n))},v.isFunction=jt,v.isNaN=function(n){return Ct(n)&&n!=+n},v.isNull=function(n){return null===n},v.isNumber=Ct,v.isObject=xt,v.isPlainObject=er,v.isRegExp=function(n){return n&&X[typeof n]&&he.call(n)==J||false},v.isString=kt,v.isUndefined=function(n){return typeof n=="undefined"
-},v.lastIndexOf=function(n,t,e){var r=n?n.length:0;for(typeof e=="number"&&(r=(0>e?Be(0,r+e):Pe(e,r-1))+1);r--;)if(n[r]===t)return r;return-1},v.mixin=Ut,v.noConflict=function(){return e._=ge,this},v.noop=Qt,v.now=ir,v.parseInt=lr,v.random=function(n,t,e){var r=null==n,u=null==t;return null==e&&(typeof n=="boolean"&&u?(e=n,n=1):u||typeof t!="boolean"||(e=t,u=true)),r&&u&&(t=1),n=+n||0,u?(t=n,n=0):t=+t||0,e||n%1||t%1?(e=Fe(),Pe(n+e*(t-n+parseFloat("1e-"+((e+"").length-1))),t)):lt(n,t)},v.reduce=Rt,v.reduceRight=Ft,v.result=function(n,t){if(n){var e=n[t];
-return jt(e)?n[t]():e}},v.runInContext=g,v.size=function(n){var t=n?n.length:0;return typeof t=="number"?t:We(n).length},v.some=$t,v.sortedIndex=Kt,v.template=function(n,t,e){var r=v.templateSettings;n=ie(n||""),e=Ze({},e,r);var u,o=Ze({},e.imports,r.imports),r=We(o),o=Et(o),i=0,l=e.interpolate||N,f="__p+='",l=ae((e.escape||N).source+"|"+l.source+"|"+(l===I?O:N).source+"|"+(e.evaluate||N).source+"|$","g");n.replace(l,function(t,e,r,o,l,c){return r||(r=o),f+=n.slice(i,c).replace(P,a),e&&(f+="'+__e("+e+")+'"),l&&(u=true,f+="';"+l+";\n__p+='"),r&&(f+="'+((__t=("+r+"))==null?'':__t)+'"),i=c+t.length,t
+},v.xor=function(){for(var n=-1,t=arguments.length;++n<t;){var e=arguments[n];if(qe(e)||dt(e))var r=r?ft(rt(r,e).concat(rt(e,r))):e}return r||[]},v.zip=Gt,v.zipObject=Jt,v.collect=Bt,v.drop=qt,v.each=Dt,v.eachRight=Nt,v.extend=Ye,v.methods=_t,v.object=Jt,v.select=At,v.tail=qt,v.unique=Wt,v.unzip=Gt,Ut(Ye({},v)),v.clone=function(n,t,e,r){return typeof t!="boolean"&&null!=t&&(r=e,e=t,t=false),Y(n,t,typeof e=="function"&&tt(e,r,1))},v.cloneDeep=function(n,t,e){return Y(n,true,typeof t=="function"&&tt(t,e,1))
+},v.contains=Ot,v.escape=function(n){return null==n?"":ie(n).replace(Qe,gt)},v.every=St,v.find=It,v.findIndex=function(n,t,e){var r=-1,u=n?n.length:0;for(t=v.createCallback(t,e,3);++r<u;)if(t(n[r],r,n))return r;return-1},v.findKey=function(n,t,e){var r;return t=v.createCallback(t,e,3),tr(n,function(n,e,u){return t(n,e,u)?(r=e,false):void 0}),r},v.findLast=function(n,t,e){var r;return t=v.createCallback(t,e,3),Nt(n,function(n,e,u){return t(n,e,u)?(r=n,false):void 0}),r},v.findLastIndex=function(n,t,e){var r=n?n.length:0;
+for(t=v.createCallback(t,e,3);r--;)if(t(n[r],r,n))return r;return-1},v.findLastKey=function(n,t,e){var r;return t=v.createCallback(t,e,3),bt(n,function(n,e,u){return t(n,e,u)?(r=e,false):void 0}),r},v.has=function(n,t){return n?we.call(n,t):false},v.identity=Ht,v.indexOf=zt,v.isArguments=dt,v.isArray=qe,v.isBoolean=function(n){return true===n||false===n||n&&typeof n=="object"&&he.call(n)==L||false},v.isDate=function(n){return n&&typeof n=="object"&&he.call(n)==z||false},v.isElement=function(n){return n&&1===n.nodeType||false
+},v.isEmpty=function(n){var t=true;if(!n)return t;var e=he.call(n),r=n.length;return e==$||e==M||(Le.argsClass?e==T:dt(n))||e==G&&typeof r=="number"&&jt(n.splice)?!r:(tr(n,function(){return t=false}),t)},v.isEqual=function(n,t,e,r){return at(n,t,typeof e=="function"&&tt(e,r,2))},v.isFinite=function(n){return Ie(n)&&!De(parseFloat(n))},v.isFunction=jt,v.isNaN=function(n){return Ct(n)&&n!=+n},v.isNull=function(n){return null===n},v.isNumber=Ct,v.isObject=xt,v.isPlainObject=er,v.isRegExp=function(n){return n&&X[typeof n]&&he.call(n)==J||false
+},v.isString=kt,v.isUndefined=function(n){return typeof n=="undefined"},v.lastIndexOf=function(n,t,e){var r=n?n.length:0;for(typeof e=="number"&&(r=(0>e?Be(0,r+e):Pe(e,r-1))+1);r--;)if(n[r]===t)return r;return-1},v.mixin=Ut,v.noConflict=function(){return e._=ge,this},v.noop=Qt,v.now=ir,v.parseInt=lr,v.random=function(n,t,e){var r=null==n,u=null==t;return null==e&&(typeof n=="boolean"&&u?(e=n,n=1):u||typeof t!="boolean"||(e=t,u=true)),r&&u&&(t=1),n=+n||0,u?(t=n,n=0):t=+t||0,e||n%1||t%1?(e=Fe(),Pe(n+e*(t-n+parseFloat("1e-"+((e+"").length-1))),t)):lt(n,t)
+},v.reduce=Rt,v.reduceRight=Ft,v.result=function(n,t){if(n){var e=n[t];return jt(e)?n[t]():e}},v.runInContext=g,v.size=function(n){var t=n?n.length:0;return typeof t=="number"?t:We(n).length},v.some=$t,v.sortedIndex=Kt,v.template=function(n,t,e){var r=v.templateSettings;n=ie(n||""),e=Ze({},e,r);var u,o=Ze({},e.imports,r.imports),r=We(o),o=Et(o),i=0,l=e.interpolate||N,f="__p+='",l=ae((e.escape||N).source+"|"+l.source+"|"+(l===I?O:N).source+"|"+(e.evaluate||N).source+"|$","g");n.replace(l,function(t,e,r,o,l,c){return r||(r=o),f+=n.slice(i,c).replace(P,a),e&&(f+="'+__e("+e+")+'"),l&&(u=true,f+="';"+l+";\n__p+='"),r&&(f+="'+((__t=("+r+"))==null?'':__t)+'"),i=c+t.length,t
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diff --git a/dist/lodash.js b/dist/lodash.js
index d653e5aed..779b157d8 100644
--- a/dist/lodash.js
+++ b/dist/lodash.js
@@ -1462,7 +1462,7 @@
 
     /**
      * Gets the appropriate "indexOf" function. If the `_.indexOf` method is
-     * customized, this method returns the custom method, otherwise it returns
+     * customized this method returns the custom method, otherwise it returns
      * the `baseIndexOf` function.
      *
      * @private
@@ -5044,9 +5044,10 @@
     }
 
     /**
-     * Creates an array of grouped elements, the first of which contains the first
-     * elements of the given arrays, the second of which contains the second
-     * elements of the given arrays, and so on.
+     * Creates an array of grouped elements, the first of which contains the
+     * first elements of the given arrays, the second of which contains the second
+     * elements of the given arrays, and so on. If a zipped value is provided its
+     * corresponding unzipped value will be returned.
      *
      * @static
      * @memberOf _
@@ -5058,6 +5059,9 @@
      *
      * _.zip(['fred', 'barney'], [30, 40], [true, false]);
      * // => [['fred', 30, true], ['barney', 40, false]]
+     *
+     * _.unzip([['fred', 30, true], ['barney', 40, false]]);
+     * // => [['fred', 'barney'], [30, 40], [true, false]]
      */
     function zip() {
       var array = arguments.length > 1 ? arguments : arguments[0],
@@ -6600,7 +6604,7 @@
     lodash.unzip = zip;
 
     // add functions to `lodash.prototype`
-    mixin(lodash);
+    mixin(assign({}, lodash));
 
     /*--------------------------------------------------------------------------*/
 
diff --git a/dist/lodash.min.js b/dist/lodash.min.js
index 85a962634..8ce51d120 100644
--- a/dist/lodash.min.js
+++ b/dist/lodash.min.js
@@ -42,7 +42,7 @@ return l(o),l(i),n},J.min=function(n,t,e){var u=1/0,o=u;if(typeof t!="function"&
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+})),e},J.union=function(){return ft(ut(arguments,true,true))},J.uniq=Pt,J.values=xt,J.where=Nt,J.without=function(n){return rt(n,p(arguments,1))},J.wrap=function(n,t){return ct(t,16,[n])},J.xor=function(){for(var n=-1,t=arguments.length;++n<t;){var e=arguments[n];if(Te(e)||yt(e))var r=r?ft(rt(r,e).concat(rt(e,r))):e}return r||[]},J.zip=Kt,J.zipObject=Lt,J.collect=Rt,J.drop=qt,J.each=St,J.eachRight=Et,J.extend=U,J.methods=bt,J.object=Lt,J.select=Nt,J.tail=qt,J.unique=Pt,J.unzip=Kt,Gt(U({},J)),J.clone=function(n,t,e,r){return typeof t!="boolean"&&null!=t&&(r=e,e=t,t=false),Z(n,t,typeof e=="function"&&tt(e,r,1))
 },J.cloneDeep=function(n,t,e){return Z(n,true,typeof t=="function"&&tt(t,e,1))},J.contains=Ct,J.escape=function(n){return null==n?"":oe(n).replace(ze,pt)},J.every=Ot,J.find=It,J.findIndex=function(n,t,e){var r=-1,u=n?n.length:0;for(t=J.createCallback(t,e,3);++r<u;)if(t(n[r],r,n))return r;return-1},J.findKey=function(n,t,e){var r;return t=J.createCallback(t,e,3),h(n,function(n,e,u){return t(n,e,u)?(r=e,false):void 0}),r},J.findLast=function(n,t,e){var r;return t=J.createCallback(t,e,3),Et(n,function(n,e,u){return t(n,e,u)?(r=n,false):void 0
 }),r},J.findLastIndex=function(n,t,e){var r=n?n.length:0;for(t=J.createCallback(t,e,3);r--;)if(t(n[r],r,n))return r;return-1},J.findLastKey=function(n,t,e){var r;return t=J.createCallback(t,e,3),mt(n,function(n,e,u){return t(n,e,u)?(r=e,false):void 0}),r},J.has=function(n,t){return n?me.call(n,t):false},J.identity=Ut,J.indexOf=Wt,J.isArguments=yt,J.isArray=Te,J.isBoolean=function(n){return true===n||false===n||n&&typeof n=="object"&&ce.call(n)==T||false},J.isDate=function(n){return n&&typeof n=="object"&&ce.call(n)==F||false
 },J.isElement=function(n){return n&&1===n.nodeType||false},J.isEmpty=function(n){var t=true;if(!n)return t;var e=ce.call(n),r=n.length;return e==$||e==P||e==D||e==q&&typeof r=="number"&&dt(n.splice)?!r:(h(n,function(){return t=false}),t)},J.isEqual=function(n,t,e,r){return ot(n,t,typeof e=="function"&&tt(e,r,2))},J.isFinite=function(n){return Ce(n)&&!Oe(parseFloat(n))},J.isFunction=dt,J.isNaN=function(n){return jt(n)&&n!=+n},J.isNull=function(n){return null===n},J.isNumber=jt,J.isObject=wt,J.isPlainObject=Pe,J.isRegExp=function(n){return n&&typeof n=="object"&&ce.call(n)==z||false
diff --git a/dist/lodash.underscore.js b/dist/lodash.underscore.js
index 0c84471f5..7785aa774 100644
--- a/dist/lodash.underscore.js
+++ b/dist/lodash.underscore.js
@@ -853,7 +853,7 @@
 
   /**
    * Gets the appropriate "indexOf" function. If the `_.indexOf` method is
-   * customized, this method returns the custom method, otherwise it returns
+   * customized this method returns the custom method, otherwise it returns
    * the `baseIndexOf` function.
    *
    * @private
@@ -3575,9 +3575,10 @@
   }
 
   /**
-   * Creates an array of grouped elements, the first of which contains the first
-   * elements of the given arrays, the second of which contains the second
-   * elements of the given arrays, and so on.
+   * Creates an array of grouped elements, the first of which contains the
+   * first elements of the given arrays, the second of which contains the second
+   * elements of the given arrays, and so on. If a zipped value is provided its
+   * corresponding unzipped value will be returned.
    *
    * @static
    * @memberOf _
@@ -3589,6 +3590,9 @@
    *
    * _.zip(['fred', 'barney'], [30, 40], [true, false]);
    * // => [['fred', 30, true], ['barney', 40, false]]
+   *
+   * _.unzip([['fred', 30, true], ['barney', 40, false]]);
+   * // => [['fred', 'barney'], [30, 40], [true, false]]
    */
   function zip() {
     var index = -1,
@@ -4900,7 +4904,7 @@
   /*--------------------------------------------------------------------------*/
 
   // add functions to `lodash.prototype`
-  mixin(lodash);
+  mixin(assign({}, lodash));
 
   /**
    * The semantic version number.
diff --git a/dist/lodash.underscore.min.js b/dist/lodash.underscore.min.js
index e65912447..2b242f5de 100644
--- a/dist/lodash.underscore.min.js
+++ b/dist/lodash.underscore.min.js
@@ -35,5 +35,5 @@ for(r||!e||Cr(n[0])||(r=[]);++t<e;){var o=n[t];r?u[o]=r[t]:o&&(u[o[0]]=o[1])}ret
 },u.isElement=function(n){return n&&1===n.nodeType||false},u.isEmpty=E,u.isEqual=function(n,r){return s(n,r)},u.isFinite=function(n){return qr(n)&&!Dr(parseFloat(n))},u.isFunction=A,u.isNaN=function(n){return S(n)&&n!=+n},u.isNull=function(n){return null===n},u.isNumber=S,u.isObject=O,u.isRegExp=function(n){return n&&vr[typeof n]&&Er.call(n)==gr||false},u.isString=N,u.isUndefined=function(n){return typeof n=="undefined"},u.lastIndexOf=function(n,r,t){var e=n?n.length:0;for(typeof t=="number"&&(e=(0>t?Mr(0,e+t):$r(t,e-1))+1);e--;)if(n[e]===r)return e;
 return-1},u.mixin=Z,u.noConflict=function(){return mr._=Tr,this},u.random=function(n,r){return null==n&&null==r&&(r=1),n=+n||0,null==r?(r=n,n=0):r=+r||0,n+Sr(Wr()*(r-n+1))},u.reduce=W,u.reduceRight=z,u.result=function(n,r){if(n){var t=n[r];return A(t)?n[r]():t}},u.size=function(n){var r=n?n.length:0;return typeof r=="number"?r:Ur(n).length},u.some=P,u.sortedIndex=J,u.template=function(n,r,e){var o=u,i=o.templateSettings;n=(n||"")+"",e=j({},e,i);var f=0,a="__p+='",i=e.variable;n.replace(RegExp((e.escape||or).source+"|"+(e.interpolate||or).source+"|"+(e.evaluate||or).source+"|$","g"),function(r,e,u,o,i){return a+=n.slice(f,i).replace(ir,t),e&&(a+="'+_.escape("+e+")+'"),o&&(a+="';"+o+";\n__p+='"),u&&(a+="'+((__t=("+u+"))==null?'':__t)+'"),f=i+r.length,r
 }),a+="';",i||(i="obj",a="with("+i+"||{}){"+a+"}"),a="function("+i+"){var __t,__p='',__j=Array.prototype.join;function print(){__p+=__j.call(arguments,'')}"+a+"return __p}";try{var l=Function("_","return "+a)(o)}catch(c){throw c.source=a,c}return r?l(r):(l.source=a,l)},u.unescape=function(n){return null==n?"":(n+"").replace(Hr,d)},u.uniqueId=function(n){var r=++tr+"";return n?n+r:r},u.all=B,u.any=P,u.detect=q,u.findWhere=function(n,r){return U(n,r,true)},u.foldl=W,u.foldr=z,u.include=k,u.inject=W,u.first=V,u.last=function(n,r,t){var u=0,o=n?n.length:0;
-if(typeof r!="number"&&null!=r){var i=o;for(r=X(r,t,3);i--&&r(n[i],i,n);)u++}else if(u=r,null==u||t)return n?n[o-1]:rr;return e(n,Mr(0,o-u))},u.sample=function(n,r,t){return n&&typeof n.length!="number"&&(n=R(n)),null==r||t?n?n[0+Sr(Wr()*(n.length-1-0+1))]:rr:(n=C(n),n.length=$r(Mr(0,r),n.length),n)},u.take=V,u.head=V,Z(u),u.VERSION="2.4.1",u.prototype.chain=function(){return this.__chain__=true,this},u.prototype.value=function(){return this.__wrapped__},D("pop push reverse shift sort splice unshift".split(" "),function(n){var r=jr[n];
+if(typeof r!="number"&&null!=r){var i=o;for(r=X(r,t,3);i--&&r(n[i],i,n);)u++}else if(u=r,null==u||t)return n?n[o-1]:rr;return e(n,Mr(0,o-u))},u.sample=function(n,r,t){return n&&typeof n.length!="number"&&(n=R(n)),null==r||t?n?n[0+Sr(Wr()*(n.length-1-0+1))]:rr:(n=C(n),n.length=$r(Mr(0,r),n.length),n)},u.take=V,u.head=V,Z(w({},u)),u.VERSION="2.4.1",u.prototype.chain=function(){return this.__chain__=true,this},u.prototype.value=function(){return this.__wrapped__},D("pop push reverse shift sort splice unshift".split(" "),function(n){var r=jr[n];
 u.prototype[n]=function(){var n=this.__wrapped__;return r.apply(n,arguments),zr.spliceObjects||0!==n.length||delete n[0],this}}),D(["concat","join","slice"],function(n){var r=jr[n];u.prototype[n]=function(){var n=r.apply(this.__wrapped__,arguments);return this.__chain__&&(n=new o(n),n.__chain__=true),n}}),typeof define=="function"&&typeof define.amd=="object"&&define.amd?(mr._=u, define(function(){return u})):_r&&dr?br?(dr.exports=u)._=u:_r._=u:mr._=u}).call(this);
\ No newline at end of file
diff --git a/lodash.js b/lodash.js
index b24fe86a7..69b877057 100644
--- a/lodash.js
+++ b/lodash.js
@@ -6971,7 +6971,7 @@
     lodash.unzip = zip;
 
     // add functions to `lodash.prototype`
-    mixin(lodash);
+    mixin(assign({}, lodash));
 
     /*--------------------------------------------------------------------------*/
 
diff --git a/test/index.html b/test/index.html
index f0057617b..2a40fa446 100644
--- a/test/index.html
+++ b/test/index.html
@@ -18,6 +18,9 @@
 		<div id="qunit"></div>
 		<div id="exports"></div>
 		<script>
+			// add extensions
+			Function.prototype._method = function() {};
+
 			// set bad shims
 			Array._isArray = Array.isArray;
 			Array.isArray = function() {};
@@ -40,12 +43,12 @@
 			Object._keys = Object.keys;
 			Object.keys = function() {};
 
-			// load Lo-Dash and expose it to the bad shims
+			// load Lo-Dash and expose it to the bad extensions/shims
 			document.write('<script src="' + (ui.isModularize ? '../lodash.js' : ui.buildPath) + '"><\/script>');
 		</script>
 		<script>
-			// store Lo-Dash to test for bad shim detection
-			var lodashBadShim = window._;
+			// store Lo-Dash to test for bad extensions/shims
+			var lodashBizarro = window._;
 
 			// restore native methods
 			if (Array._isArray) {
@@ -86,6 +89,7 @@
 			delete Array._isArray;
 			delete Date._now;
 			delete Function.prototype._bind;
+			delete Function.prototype._method;
 			delete Object._create;
 			delete Object._defineProperty;
 			delete Object._getPrototypeOf;
diff --git a/test/saucelabs.js b/test/saucelabs.js
index 4b91026e7..ce2104ab0 100644
--- a/test/saucelabs.js
+++ b/test/saucelabs.js
@@ -247,7 +247,7 @@
     var options = {
       'build': build,
       'framework': 'qunit',
-      'idle-timeout': 300,
+      'idle-timeout': 240,
       'max-duration': 480,
       'name': sessionName,
       'public': 'public',
diff --git a/test/test.js b/test/test.js
index 70ca1c41d..7036941f0 100644
--- a/test/test.js
+++ b/test/test.js
@@ -1,8 +1,8 @@
 ;(function(root, undefined) {
   'use strict';
 
-  /** Used to store Lo-Dash to test for bad shim detection */
-  var lodashBadShim = root.lodashBadShim;
+  /** Used to store Lo-Dash to test for bad extensions/shims */
+  var lodashBizarro = root.lodashBizarro;
 
   /** Method and object shortcuts */
   var phantom = root.phantom,
@@ -216,6 +216,9 @@
           '})'
         ].join('\n')));
 
+        // add extensions
+        Function.prototype._method = function() {};
+
         // set bad shims
         Array._isArray = Array.isArray;
         Array.isArray = function() {};
@@ -238,8 +241,8 @@
         Object._keys = Object.keys;
         Object.keys = function() {};
 
-        // load Lo-Dash and expose it to the bad shims
-        lodashBadShim = (lodashBadShim = require(filePath))._ || lodashBadShim;
+        // load Lo-Dash and expose it to the bad extensions/shims
+        lodashBizarro = (lodashBizarro = require(filePath))._ || lodashBizarro;
 
         // restore native methods
         Array.isArray = Array._isArray;
@@ -253,6 +256,7 @@
         delete Array._isArray;
         delete Date._now;
         delete Function.prototype._bind;
+        delete Function.prototype._method;
         delete Object._create;
         delete Object._defineProperty;
         delete Object._getPrototypeOf;
@@ -353,7 +357,16 @@
       }
     });
 
-    test('avoids overwritten native methods', 7, function() {
+    test('should not add `Function.prototype` extensions to lodash', 1, function() {
+      if (lodashBizarro) {
+        equal('_method' in lodashBizarro, false);
+      }
+      else {
+        skipTest(1);
+      }
+    });
+
+    test('should avoid overwritten native methods', 7, function() {
       function Foo() {}
 
       function message(methodName) {
@@ -361,23 +374,23 @@
       }
       var object = { 'a': true };
 
-      if (lodashBadShim) {
+      if (lodashBizarro) {
         try {
-          actual = [lodashBadShim.isArray([]), lodashBadShim.isArray({ 'length': 0 })];
+          actual = [lodashBizarro.isArray([]), lodashBizarro.isArray({ 'length': 0 })];
         } catch(e) {
           actual = null;
         }
         deepEqual(actual, [true, false], message('Array.isArray'));
 
         try {
-          actual = lodashBadShim.now();
+          actual = lodashBizarro.now();
         } catch(e) {
           actual = null;
         }
         ok(typeof actual == 'number', message('Date.now'));
 
         try {
-          actual = [lodashBadShim.create(Foo.prototype, object), lodashBadShim.create()];
+          actual = [lodashBizarro.create(Foo.prototype, object), lodashBizarro.create()];
         } catch(e) {
           actual = null;
         }
@@ -385,21 +398,21 @@
         deepEqual(actual[1], {}, message('Object.create'));
 
         try {
-          var actual = lodashBadShim.bind(function() { return this.a; }, object)();
+          var actual = lodashBizarro.bind(function() { return this.a; }, object)();
         } catch(e) {
           actual = null;
         }
         ok(actual, message('Object.defineProperty'));
 
         try {
-          actual = [lodashBadShim.isPlainObject({}), lodashBadShim.isPlainObject([])];
+          actual = [lodashBizarro.isPlainObject({}), lodashBizarro.isPlainObject([])];
         } catch(e) {
           actual = null;
         }
         deepEqual(actual, [true, false], message('Object.getPrototypeOf'));
 
         try {
-          actual = [lodashBadShim.keys(object), lodashBadShim.keys()];
+          actual = [lodashBizarro.keys(object), lodashBizarro.keys()];
         } catch(e) {
           actual = null;
         }
@@ -1372,10 +1385,10 @@
 
       if (defineProperty && _.support.funcDecomp) {
         _.createCallback(a, object);
-        ok('__bindData__' in a)
+        ok('__bindData__' in a);
 
         _.createCallback(b, object);
-        ok(!('__bindData__' in b));
+        equal('__bindData__' in b, false);
 
         if (_.support.funcNames) {
           _.support.funcNames = false;
@@ -4388,11 +4401,10 @@
       strictEqual(_.isPlainObject({}), true);
     });
 
-    test('should return `false` for Object objects without a [[Class]] of "Object"', 4, function() {
+    test('should return `false` for Object objects without a [[Class]] of "Object"', 3, function() {
       strictEqual(_.isPlainObject(arguments), false);
       strictEqual(_.isPlainObject(Error), false);
       strictEqual(_.isPlainObject(Math), false);
-      strictEqual(_.isPlainObject(root), false);
     });
 
     test('should return `false` for non objects', 3, function() {