Shadow Walker is an active hacker on MSP (UK). They arrived in April 2015, apparently here for revenge, and seemingly thinks that they own MSP. Despite not being very well accomplished or known, they have left quite an impact on users.
HackingsShadow hacks because on their main account they were not liked, so while in annoyance they deleted their account, and made a hacker account "Shadow Walker(d)" and now they are starting to hack innocent people. They had at one point stopped hacking, but after many users seemed to hate on them, they reverted back to hacking.
Trying to look scary, and unfortunately, unable to do so, they use the style of 'goth' to try and scare users. Like many hackers, they think constantly using the devil face smiley is scary. They call themselves, "The Devil" with their quote being, "Give me your shadow or you're gone forever."