Ahtal-Ka, Pavilion Mantis

When Ahtal-Ka, Pavilion Mantis enters the battlefield, create X Junk tokens.

At the beginning of each end step, if you control a
desert and you don't control a vehicle, create a Junk
token.

Sacrifice five Junk tokens: create a 10/10 colorless legendary artifact vehicle token named Walking
Fortress with crew 5 and "At the beginning of each
end step, sacrifice an artifact."