So .... I flashed the mantaray-lrx21p image from Nexus Factory Images on my Nexus 10 (16GB Wifi) and it's stuck in a bootloop.
No problem, I thought, I can get into fastboot and fix it, right? Maybe do a wipe and try again? Yeah, not so fast. I get the bootloader screen, but the only option is 'Start' which just boots into the system that bootloops.
That's OK, I'll just use fastboot to wipe it. Nope. Fastboot doesn't detect a device.
I've tried both ADB and fastboot on Mac & Linux. Same issue.