<Tr> <Th_colspan="2"> Season </Th> <Th_colspan="2"> Episodes </Th> <Th_colspan="2"> Originally aired </Th> </Tr> <Tr> <Th> First aired </Th> <Th> Last aired </Th> </Tr> <Tr> <Td> </Td> <Td_colspan="1"> 1 </Td> <Td_colspan="2"> 25 </Td> <Td_colspan="1"> April 7, 2013 (2013 - 04 - 07) </Td> <Td> September 29, 2013 (2013 - 09 - 29) </Td> </Tr> <Tr> <Td> </Td> <Td_colspan="1"> 2 </Td> <Td_colspan="2"> 12 </Td> <Td_colspan="1"> April 1, 2017 (2017 - 04 - 01) </Td> <Td> June 17, 2017 (2017 - 06 - 17) </Td> </Tr>

How many episodes are on attack on titan season 1