Polymorph Mage

'I am not going down alone.' Rowan declared.
He gave up all restraint and expanded his body mid-air to become as large as half the empire.
The ministers had pale faces as they activated all their treasured defences, but how could they protect themselves from the human calamity that had declared them dead? Just like that the empire collapsed under his weight.
'This doesn't look like hell so where am I right now?'
'It appears that I have reincarnated, let's use their sacred magic for myself in this life.'