diff --git a/src/init.cpp b/src/init.cpp
index 3798709546..6ec7dc99b7 100644
--- a/src/init.cpp
+++ b/src/init.cpp
@@ -312,7 +312,8 @@ std::string HelpMessage(HelpMessageMode mode)
     // When adding new options to the categories, please keep and ensure alphabetical ordering.
     // Do not translate _(...) -help-debug options, Many technical terms, and only a very small audience, so is unnecessary stress to translators.
     string strUsage = HelpMessageGroup(_("Options:"));
-    strUsage += HelpMessageOpt("-?", _("This help message"));
+    strUsage += HelpMessageOpt("-?", _("Print this help message and exit"));
+    strUsage += HelpMessageOpt("-version", _("Print version and exit"));
     strUsage += HelpMessageOpt("-alerts", strprintf(_("Receive and display P2P network alerts (default: %u)"), DEFAULT_ALERTS));
     strUsage += HelpMessageOpt("-alertnotify=<cmd>", _("Execute command when a relevant alert is received or we see a really long fork (%s in cmd is replaced by message)"));
     strUsage += HelpMessageOpt("-blocknotify=<cmd>", _("Execute command when the best block changes (%s in cmd is replaced by block hash)"));
@@ -421,8 +422,11 @@ std::string HelpMessage(HelpMessageMode mode)
 #endif
 
     strUsage += HelpMessageGroup(_("Debugging/Testing options:"));
+    strUsage += HelpMessageOpt("-uacomment=<cmt>", _("Append comment to the user agent string"));
     if (showDebug)
     {
+        strUsage += HelpMessageOpt("-checkblockindex", strprintf("Do a full consistency check for mapBlockIndex, setBlockIndexCandidates, chainActive and mapBlocksUnlinked occasionally. Also sets -checkmempool. (default: %u)", Params().DefaultConsistencyChecks()));
+        strUsage += HelpMessageOpt("-checkmempool=<n>", strprintf("Run checks every <n> transactions. (default: %u)", Params().DefaultConsistencyChecks()));
         strUsage += HelpMessageOpt("-checkpoints", strprintf("Disable expensive verification for known chain history (default: %u)", DEFAULT_CHECKPOINTS_ENABLED));
 #ifdef ENABLE_WALLET
         strUsage += HelpMessageOpt("-dblogsize=<n>", strprintf("Flush wallet database activity from memory to disk log every <n> megabytes (default: %u)", DEFAULT_WALLET_DBLOGSIZE));
@@ -445,6 +449,8 @@ std::string HelpMessage(HelpMessageMode mode)
         debugCategories += ", qt";
     strUsage += HelpMessageOpt("-debug=<category>", strprintf(_("Output debugging information (default: %u, supplying <category> is optional)"), 0) + ". " +
         _("If <category> is not supplied or if <category> = 1, output all debugging information.") + _("<category> can be:") + " " + debugCategories + ".");
+    if (showDebug)
+        strUsage += HelpMessageOpt("-nodebug", "Turn off debugging messages, same as -debug=0");
     strUsage += HelpMessageOpt("-gen", strprintf(_("Generate coins (default: %u)"), DEFAULT_GENERATE));
     strUsage += HelpMessageOpt("-genproclimit=<n>", strprintf(_("Set the number of threads for coin generation if enabled (-1 = all cores, default: %d)"), DEFAULT_GENERATE_THREADS));
     strUsage += HelpMessageOpt("-help-debug", _("Show all debugging options (usage: --help -help-debug)"));
@@ -453,6 +459,7 @@ std::string HelpMessage(HelpMessageMode mode)
     if (showDebug)
     {
         strUsage += HelpMessageOpt("-logtimemicros", strprintf("Add microsecond precision to debug timestamps (default: %u)", DEFAULT_LOGTIMEMICROS));
+        strUsage += HelpMessageOpt("-mocktime=<n>", "Replace actual time with <n> (default: 0)");
         strUsage += HelpMessageOpt("-limitfreerelay=<n>", strprintf("Continuously rate-limit free transactions to <n>*1000 bytes per minute (default: %u)", DEFAULT_LIMITFREERELAY));
         strUsage += HelpMessageOpt("-relaypriority", strprintf("Require high priority for relaying free or low-fee transactions (default: %u)", DEFAULT_RELAYPRIORITY));
         strUsage += HelpMessageOpt("-maxsigcachesize=<n>", strprintf("Limit size of signature cache to <n> MiB (default: %u)", DEFAULT_MAX_SIG_CACHE_SIZE));
@@ -488,6 +495,7 @@ std::string HelpMessage(HelpMessageMode mode)
     strUsage += HelpMessageOpt("-server", _("Accept command line and JSON-RPC commands"));
     strUsage += HelpMessageOpt("-rest", strprintf(_("Accept public REST requests (default: %u)"), DEFAULT_REST_ENABLE));
     strUsage += HelpMessageOpt("-rpcbind=<addr>", _("Bind to given address to listen for JSON-RPC connections. Use [host]:port notation for IPv6. This option can be specified multiple times (default: bind to all interfaces)"));
+    strUsage += HelpMessageOpt("-rpccookiefile=<loc>", _("Location of the auth cookie (default: data dir)"));
     strUsage += HelpMessageOpt("-rpcuser=<user>", _("Username for JSON-RPC connections"));
     strUsage += HelpMessageOpt("-rpcpassword=<pw>", _("Password for JSON-RPC connections"));
     strUsage += HelpMessageOpt("-rpcauth=<userpw>", _("Username and hashed password for JSON-RPC connections. The field <userpw> comes in the format: <USERNAME>:<SALT>$<HASH>. A canonical python script is included in share/rpcuser. This option can be specified multiple times"));