It’s Tardimus Prime! The Sonic Screwdriver will be the least of the Time Lord’s enemies’ worries if the TARDIS actually transformed into Optimus Prime. It’ll still be bigger on the inside though.
Gotta love the bowtie. Jason Casteel came up with the art after
seeing a Police Box transform being beaten senseless by a Dalek a discussion with his brother about making a TARDIS Halloween costume. You can get the shirt for only $10 (USD) at GraphicLab T-shirt. Or you might not, because as of this writing there’s only a few more hours left before the shirt goes off sale.