DesignSmoke

Anti-Spam Zapper will automatically remove spam comments and block spambots without annoying CAPTCHAs.
Protect your website from spam comments and automated spam using this free WordPress anti-spam plugin.
Features
<ul>
<li>Protect Comments</li>
<li>Block Spambots</li>
<li>Marks comments as spam, without deleting them, just-in-case there’s a false positive</li>
<li>Nothing to fill out, completely silent action</li>
</ul>
FAQ
<ul>
<li>Does this require javascript?</li>
<li>
Yes, however the vast majority of users have javascript enabled (over 99%). Users with javascript disabled will be shown a message, just to make sure nothing is lost.
</li>
<li>
Can I modify this plugin?
</li>
<li>Yes! The plugin is <a href="http://www.gnu.org/licenses/gpl-2.0.html" rel="nofollow ugc">licensed under the GPLv2 License</a>.</li>
</ul>
Upgrade to Pro
Want to protect your contact forms too? <a href="https://www.designsmoke.com/anti-spam-zapper-wordpress-plugin/" rel="nofollow ugc">Upgrade to Anti-Spam Zapper PRO by DesignSmoke</a> to stop all spam comments and form submissions on your WordPress website or WooCommerce store.

Anti-Spam Zapper for WordPress

Anti-Spam Zapper will automatically remove spam comments and block spambots without annoying CAPTCHAs. Protect your…

Steve

<h3>Premier Spam Prevention Plugin for WordPress</h3>
<h4>The QUADRUPLE Crown of Spam protection runs every comment submission through a gauntlet of tests, all invisible and harmless to human visitors, all highly efficient at detecting automated spam:</h4>
<ol>
<li>The clocker destroys anyone submitting forms too quickly to be human.</li>
<li>The bouncer eliminates anyone caught trying to sneak in with form fields only spammers would use. </li>
<li>The planter silently distributes secret codes to genuine human commenters which are then verified upon submission. </li>
<li>The surgeon optionally severs your websites ability to receive trackback spam.</li>
</ol>
<h4>Special Bonus!</h4>
Not only does SpamLord protect your website, it also enables you to get the last word in. Now you can reply to would-be spammers with options such as:
<ul>
<li>a curated selection of tastefully sarcastic comments (now in 13 languages covering the regions that produce the most spam)</li>
<li>a false positive so they think it worked (and won’t try harder next time)</li>
<li>anything you want using the custom response option</li>
</ul>

SpamLord

Upon activation, SpamLord eliminates the potential for automated spam comments, as well as trackback spam.

Anti-Spam Zapper for WordPress vs SpamLord