Validate entries don't match "First Name", "asdf", "90210", &quot

Out of the box Gravity Forms validation is specific to the type of field you are using and designed for general use. For custom use cases and custom validation you can use the gform_validation hook and do whatever you want as far as validation goes. Using custom code and the gform_validation hook you have complete control.

There is a tutorial on how to implement custom validation here:

http://www.gravityhelp.com/documentation/page/Using_the_Gravity_Forms_%22gform_validation%22_Hook

The gform_validation hook is documented here:

http://www.gravityhelp.com/documentation/page/Gform_validation

Any custom code you write would go either in your themes functions.php file, or in a custom plugin you create and activate.