Sepultura are the final act to be announced for the inaugural Hammerfest.
The Brazlian heavy metal quartet will co-headline the Saturday (25 April) night line-up with Saxon.
Opeth will headline the Friday night with Hammerfall, Paradise Lost, Skindred, Cathedral, Alestorm, Grand Magus, Sabbat and many more also set to play the two-day event.
Organisers have also announced that they have changed their licence to allow entry to 16 and 17 year olds.
Hammerfest 2009 will take place at Pontins, Prestatyn Sand, North Wales from 24-25 April.
Only day tickets and VIP passes are still available with prices starting at £45 per day.
Hammerfest is an indoor metal and rock festival boasting an incredible 50 live acts performing across six arenas in just two days.