Aberavon may have won the Welsh National League Division One title for the last two seasons, but they will remain in the division against next season.
Caerphilly, having won the first leg of the play-off match by 17-13 at Aberavon, set about taming the Wizards and ran in six tries in their second leg success at Virginia Park.
The 49-14 win gave Caerphilly an overall aggregate of 66-27 and fly half Luke Richards led the way with 24 points from a try, five conversions and a hat-trick of penalty goals.
Other tries for Caerphilly came from Taunaholo Taufahema, Simon Grainger, Sione Mone Tuipulotu, John Colderley and a penalty try with former Wales full back Matthew Back crossing twice for Aberavon and New Zealander Scott Leighton goaling both tries.
Nearly 40 players were involved in the first Wales Under 18 training session of the season. WRU National Performance Manager Gethin Watts is excited at the potential shown by the group and expects the Regional Under 18 Championship to hone their skills even further.