[EDIT] After letting the battery run dry again last night, plugging my phone back into my laptop booted into download mode, again with the same display as below. Fastboot again recognised the device & after doing some searching, I'd seen another suggestion somewhere else I hadn't yet tried, which was forcing the phone to partition a (to be honest I couldn't even remember which partition I'd left it in from the attempted root)
The command is "fastboot set_active a && fastboot reboot"
I did this as soon as I was able to, rather than leaving it charging (this may be unrelated, but worth considering if you're still stuck)
after this, I got to the Razer logo screen lock (instead of the blank screen lock below), I was then able to follow Razer's instructions - which are linked in one of the comments on the link from the 2nd post here (hope that makes sense)
Now I'm happy to report everything is working, back to factory
I hope this can help someone else [EDIT]
I'm unfortunately in the same position, did you have any luck flashing back to factory?
I also tried following the guide from the 2nd link, these were the steps I took:
(I can confirm my bootloader is unlocked & critical also unlocked)
1. allowed battery to run dry
2. plugged into laptop whilst holding volume -
3. phone now in download mode with battery charge symbol on screen, I left it some time to charge but noticed it got stuck as per the screenshot (for approx. 6 hours)
4. device not recognised by adb, but recognised by fastboot
5. phone not accepting any fastboot commands, when attempting 'flash_all.bat' just hangs on the first line (flash partition:0 gpt_both0.bin), I have to close command line & reopen to try anything else, however whatever I try I get the same result, so basically the only responses I'm getting from fastboot are that it is aware of the device and confirms the bootloader incl. critical is unlocked
My next thought was the perhaps the phone attempted to boot once it reached the picture charge level and therefore locked in the same way it had initially on the razer logo. Should I attempt flashing the factory image immediately once the phone enters download mode, rather than allowing it to continue charging until it's flashed? Any ideas would be greatly appreciated!
Cheers