cll.proxy.mythic-beasts.com has no MX records.
Question and response
Question
dig cll.proxy.mythic-beasts.com. MX
Answer
The response has no answer records.
Authority
mythic-beasts.com. 3600 SOA ns2.mythic-beasts.com. admin.beasts.org. 2010171374 21600 3600 604800 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0