diff --git a/docs/acf-core/co/aikar/commands/CommandCompletions.html b/docs/acf-core/co/aikar/commands/CommandCompletions.html
index 254def867..1b9ca3b01 100644
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+++ b/docs/acf-core/co/aikar/commands/CommandCompletions.html
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 </tr>
 <tr id="i2" class="altColor">
 <td class="colFirst"><code><a href="../../../co/aikar/commands/CommandCompletions.CommandCompletionHandler.html" title="interface in co.aikar.commands">CommandCompletions.CommandCompletionHandler</a></code></td>
-<td class="colLast"><code><span class="memberNameLink"><a href="../../../co/aikar/commands/CommandCompletions.html#registerStaticCompletion-java.lang.String-java.util.List-">registerStaticCompletion</a></span>(<a href="https://docs.oracle.com/javase/8/docs/api/java/lang/String.html?is-external=true" title="class or interface in java.lang">String</a>&nbsp;id,
-                        <a href="https://docs.oracle.com/javase/8/docs/api/java/util/List.html?is-external=true" title="class or interface in java.util">List</a>&lt;<a href="https://docs.oracle.com/javase/8/docs/api/java/lang/String.html?is-external=true" title="class or interface in java.lang">String</a>&gt;&nbsp;completions)</code>
+<td class="colLast"><code><span class="memberNameLink"><a href="../../../co/aikar/commands/CommandCompletions.html#registerStaticCompletion-java.lang.String-java.util.Collection-">registerStaticCompletion</a></span>(<a href="https://docs.oracle.com/javase/8/docs/api/java/lang/String.html?is-external=true" title="class or interface in java.lang">String</a>&nbsp;id,
+                        <a href="https://docs.oracle.com/javase/8/docs/api/java/util/Collection.html?is-external=true" title="class or interface in java.util">Collection</a>&lt;<a href="https://docs.oracle.com/javase/8/docs/api/java/lang/String.html?is-external=true" title="class or interface in java.lang">String</a>&gt;&nbsp;completions)</code>
 <div class="block">Register a static list of command completions that will never change</div>
 </td>
 </tr>
@@ -210,7 +210,7 @@ <h3>Method Summary</h3>
 <tr id="i5" class="rowColor">
 <td class="colFirst"><code><a href="../../../co/aikar/commands/CommandCompletions.CommandCompletionHandler.html" title="interface in co.aikar.commands">CommandCompletions.CommandCompletionHandler</a></code></td>
 <td class="colLast"><code><span class="memberNameLink"><a href="../../../co/aikar/commands/CommandCompletions.html#registerStaticCompletion-java.lang.String-java.util.function.Supplier-">registerStaticCompletion</a></span>(<a href="https://docs.oracle.com/javase/8/docs/api/java/lang/String.html?is-external=true" title="class or interface in java.lang">String</a>&nbsp;id,
-                        <a href="https://docs.oracle.com/javase/8/docs/api/java/util/function/Supplier.html?is-external=true" title="class or interface in java.util.function">Supplier</a>&lt;<a href="https://docs.oracle.com/javase/8/docs/api/java/util/List.html?is-external=true" title="class or interface in java.util">List</a>&lt;<a href="https://docs.oracle.com/javase/8/docs/api/java/lang/String.html?is-external=true" title="class or interface in java.lang">String</a>&gt;&gt;&nbsp;supplier)</code>
+                        <a href="https://docs.oracle.com/javase/8/docs/api/java/util/function/Supplier.html?is-external=true" title="class or interface in java.util.function">Supplier</a>&lt;<a href="https://docs.oracle.com/javase/8/docs/api/java/util/Collection.html?is-external=true" title="class or interface in java.util">Collection</a>&lt;<a href="https://docs.oracle.com/javase/8/docs/api/java/lang/String.html?is-external=true" title="class or interface in java.lang">String</a>&gt;&gt;&nbsp;supplier)</code>
 <div class="block">Register a static list of command completions that will never change.</div>
 </td>
 </tr>
@@ -339,7 +339,7 @@ <h4>registerStaticCompletion</h4>
 <li class="blockList">
 <h4>registerStaticCompletion</h4>
 <pre>public&nbsp;<a href="../../../co/aikar/commands/CommandCompletions.CommandCompletionHandler.html" title="interface in co.aikar.commands">CommandCompletions.CommandCompletionHandler</a>&nbsp;<a href="../../../src-html/co/aikar/commands/CommandCompletions.html#line.131">registerStaticCompletion</a>(<a href="https://docs.oracle.com/javase/8/docs/api/java/lang/String.html?is-external=true" title="class or interface in java.lang">String</a>&nbsp;id,
-                                                                            <a href="https://docs.oracle.com/javase/8/docs/api/java/util/function/Supplier.html?is-external=true" title="class or interface in java.util.function">Supplier</a>&lt;<a href="https://docs.oracle.com/javase/8/docs/api/java/util/List.html?is-external=true" title="class or interface in java.util">List</a>&lt;<a href="https://docs.oracle.com/javase/8/docs/api/java/lang/String.html?is-external=true" title="class or interface in java.lang">String</a>&gt;&gt;&nbsp;supplier)</pre>
+                                                                            <a href="https://docs.oracle.com/javase/8/docs/api/java/util/function/Supplier.html?is-external=true" title="class or interface in java.util.function">Supplier</a>&lt;<a href="https://docs.oracle.com/javase/8/docs/api/java/util/Collection.html?is-external=true" title="class or interface in java.util">Collection</a>&lt;<a href="https://docs.oracle.com/javase/8/docs/api/java/lang/String.html?is-external=true" title="class or interface in java.lang">String</a>&gt;&gt;&nbsp;supplier)</pre>
 <div class="block">Register a static list of command completions that will never change. The list is obtained from the supplier
  immediately as part of this method call.</div>
 <dl>
@@ -350,14 +350,14 @@ <h4>registerStaticCompletion</h4>
 </dl>
 </li>
 </ul>
-<a name="registerStaticCompletion-java.lang.String-java.util.List-">
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 <pre>public&nbsp;<a href="../../../co/aikar/commands/CommandCompletions.CommandCompletionHandler.html" title="interface in co.aikar.commands">CommandCompletions.CommandCompletionHandler</a>&nbsp;<a href="../../../src-html/co/aikar/commands/CommandCompletions.html#line.142">registerStaticCompletion</a>(<a href="https://docs.oracle.com/javase/8/docs/api/java/lang/String.html?is-external=true" title="class or interface in java.lang">String</a>&nbsp;id,
-                                                                            <a href="https://docs.oracle.com/javase/8/docs/api/java/util/List.html?is-external=true" title="class or interface in java.util">List</a>&lt;<a href="https://docs.oracle.com/javase/8/docs/api/java/lang/String.html?is-external=true" title="class or interface in java.lang">String</a>&gt;&nbsp;completions)</pre>
+                                                                            <a href="https://docs.oracle.com/javase/8/docs/api/java/util/Collection.html?is-external=true" title="class or interface in java.util">Collection</a>&lt;<a href="https://docs.oracle.com/javase/8/docs/api/java/lang/String.html?is-external=true" title="class or interface in java.lang">String</a>&gt;&nbsp;completions)</pre>
 <div class="block">Register a static list of command completions that will never change</div>
 <dl>
 <dt><span class="paramLabel">Parameters:</span></dt>
diff --git a/docs/acf-core/co/aikar/commands/class-use/CommandCompletions.CommandCompletionHandler.html b/docs/acf-core/co/aikar/commands/class-use/CommandCompletions.CommandCompletionHandler.html
index 085c3daa8..f8c860331 100644
--- a/docs/acf-core/co/aikar/commands/class-use/CommandCompletions.CommandCompletionHandler.html
+++ b/docs/acf-core/co/aikar/commands/class-use/CommandCompletions.CommandCompletionHandler.html
@@ -130,8 +130,8 @@ <h3>Uses of <a href="../../../../co/aikar/commands/CommandCompletions.CommandCom
 </tr>
 <tr class="altColor">
 <td class="colFirst"><code><a href="../../../../co/aikar/commands/CommandCompletions.CommandCompletionHandler.html" title="interface in co.aikar.commands">CommandCompletions.CommandCompletionHandler</a></code></td>
-<td class="colLast"><span class="typeNameLabel">CommandCompletions.</span><code><span class="memberNameLink"><a href="../../../../co/aikar/commands/CommandCompletions.html#registerStaticCompletion-java.lang.String-java.util.List-">registerStaticCompletion</a></span>(<a href="https://docs.oracle.com/javase/8/docs/api/java/lang/String.html?is-external=true" title="class or interface in java.lang">String</a>&nbsp;id,
-                        <a href="https://docs.oracle.com/javase/8/docs/api/java/util/List.html?is-external=true" title="class or interface in java.util">List</a>&lt;<a href="https://docs.oracle.com/javase/8/docs/api/java/lang/String.html?is-external=true" title="class or interface in java.lang">String</a>&gt;&nbsp;completions)</code>
+<td class="colLast"><span class="typeNameLabel">CommandCompletions.</span><code><span class="memberNameLink"><a href="../../../../co/aikar/commands/CommandCompletions.html#registerStaticCompletion-java.lang.String-java.util.Collection-">registerStaticCompletion</a></span>(<a href="https://docs.oracle.com/javase/8/docs/api/java/lang/String.html?is-external=true" title="class or interface in java.lang">String</a>&nbsp;id,
+                        <a href="https://docs.oracle.com/javase/8/docs/api/java/util/Collection.html?is-external=true" title="class or interface in java.util">Collection</a>&lt;<a href="https://docs.oracle.com/javase/8/docs/api/java/lang/String.html?is-external=true" title="class or interface in java.lang">String</a>&gt;&nbsp;completions)</code>
 <div class="block">Register a static list of command completions that will never change</div>
 </td>
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@@ -152,7 +152,7 @@ <h3>Uses of <a href="../../../../co/aikar/commands/CommandCompletions.CommandCom
 <tr class="rowColor">
 <td class="colFirst"><code><a href="../../../../co/aikar/commands/CommandCompletions.CommandCompletionHandler.html" title="interface in co.aikar.commands">CommandCompletions.CommandCompletionHandler</a></code></td>
 <td class="colLast"><span class="typeNameLabel">CommandCompletions.</span><code><span class="memberNameLink"><a href="../../../../co/aikar/commands/CommandCompletions.html#registerStaticCompletion-java.lang.String-java.util.function.Supplier-">registerStaticCompletion</a></span>(<a href="https://docs.oracle.com/javase/8/docs/api/java/lang/String.html?is-external=true" title="class or interface in java.lang">String</a>&nbsp;id,
-                        <a href="https://docs.oracle.com/javase/8/docs/api/java/util/function/Supplier.html?is-external=true" title="class or interface in java.util.function">Supplier</a>&lt;<a href="https://docs.oracle.com/javase/8/docs/api/java/util/List.html?is-external=true" title="class or interface in java.util">List</a>&lt;<a href="https://docs.oracle.com/javase/8/docs/api/java/lang/String.html?is-external=true" title="class or interface in java.lang">String</a>&gt;&gt;&nbsp;supplier)</code>
+                        <a href="https://docs.oracle.com/javase/8/docs/api/java/util/function/Supplier.html?is-external=true" title="class or interface in java.util.function">Supplier</a>&lt;<a href="https://docs.oracle.com/javase/8/docs/api/java/util/Collection.html?is-external=true" title="class or interface in java.util">Collection</a>&lt;<a href="https://docs.oracle.com/javase/8/docs/api/java/lang/String.html?is-external=true" title="class or interface in java.lang">String</a>&gt;&gt;&nbsp;supplier)</code>
 <div class="block">Register a static list of command completions that will never change.</div>
 </td>
 </tr>
diff --git a/docs/acf-core/index-all.html b/docs/acf-core/index-all.html
index 77e332505..c2436717f 100644
--- a/docs/acf-core/index-all.html
+++ b/docs/acf-core/index-all.html
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 <dd>
 <div class="block">Register a static list of command completions that will never change</div>
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-<dt><span class="memberNameLink"><a href="co/aikar/commands/CommandCompletions.html#registerStaticCompletion-java.lang.String-java.util.function.Supplier-">registerStaticCompletion(String, Supplier&lt;List&lt;String&gt;&gt;)</a></span> - Method in class co.aikar.commands.<a href="co/aikar/commands/CommandCompletions.html" title="class in co.aikar.commands">CommandCompletions</a></dt>
+<dt><span class="memberNameLink"><a href="co/aikar/commands/CommandCompletions.html#registerStaticCompletion-java.lang.String-java.util.function.Supplier-">registerStaticCompletion(String, Supplier&lt;Collection&lt;String&gt;&gt;)</a></span> - Method in class co.aikar.commands.<a href="co/aikar/commands/CommandCompletions.html" title="class in co.aikar.commands">CommandCompletions</a></dt>
 <dd>
 <div class="block">Register a static list of command completions that will never change.</div>
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+<dt><span class="memberNameLink"><a href="co/aikar/commands/CommandCompletions.html#registerStaticCompletion-java.lang.String-java.util.Collection-">registerStaticCompletion(String, Collection&lt;String&gt;)</a></span> - Method in class co.aikar.commands.<a href="co/aikar/commands/CommandCompletions.html" title="class in co.aikar.commands">CommandCompletions</a></dt>
 <dd>
 <div class="block">Register a static list of command completions that will never change</div>
 </dd>
diff --git a/docs/acf-core/src-html/co/aikar/commands/CommandCompletions.AsyncCommandCompletionHandler.html b/docs/acf-core/src-html/co/aikar/commands/CommandCompletions.AsyncCommandCompletionHandler.html
index ca4306a78..d0b80d7c0 100644
--- a/docs/acf-core/src-html/co/aikar/commands/CommandCompletions.AsyncCommandCompletionHandler.html
+++ b/docs/acf-core/src-html/co/aikar/commands/CommandCompletions.AsyncCommandCompletionHandler.html
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index ca4306a78..d0b80d7c0 100644
--- a/docs/acf-core/src-html/co/aikar/commands/CommandCompletions.CommandCompletionHandler.html
+++ b/docs/acf-core/src-html/co/aikar/commands/CommandCompletions.CommandCompletionHandler.html
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index ca4306a78..d0b80d7c0 100644
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