If I try to open one of your missing images, I get an error
IMG is http://mightymarvelgeeks.net/wp-content/themes/itheme2/themify/img.php?src=http://mightymarvelgeeks.net/wp-content/uploads/2017/03/MMG-159-icon-copy-1.jpg&w=131&h=131
error is
Warning: unlink(../cache/wordthumb_ext_35c995666eb08d0d4e131a0419d67570.wordthumb.txt): No such file or directory in /home3/wbgpmike/public_html/mightymarvelgeeks.net/wp-content/themes/itheme2/themify/img.php on line 792
Warning: Cannot modify header information - headers already sent by (output started at /home3/wbgpmike/public_html/mightymarvelgeeks.net/wp-content/themes/itheme2/themify/img.php:792) in /home3/wbgpmike/public_html/mightymarvelgeeks.net/wp-content/themes/itheme2/themify/img.php on line 316
A WordThumb error has occured
The following error(s) occured:
The remote file is not a valid image.
Query String : src=http://mightymarvelgeeks.net/wp-content/uploads/2017/03/MMG-159-icon-copy-1.jpg&w=131&h=131
WordThumb version : 1.07
This may be a plugin or theme conflict. Please attempt to disable all plugins, and use one of the default (Twenty*) themes. If the problem goes away, enable them one by one to identify the source of your troubles.
See http://www.wpbeginner.com/plugins/how-to-deactivate-all-plugins-when-not-able-to-access-wp-admin/