The likes of ex-Catatonia leading lady Cerys Matthews and hip-hop artist Dante Santiago complete the line up of mentors, who will help the four coaches with their acts in the forthcoming Battle Rounds.
Santaigo, who was once in a group with Will.I.Am called Atban Klann - which he left in 1995 before they became the Black Eyed Peas - will act as Will's right-hand man, while Ana Matronic will help mentor Jessie J's team.
The Battle Rounds are when each coach whittles down their ten acts to just five finalists for the Live Shows, where the hopefuls will go head-to-head by performing the same tunes in order to impress their coach and guest mentor.
In other related news, Will.I.Am has allegedly been warned to 'cool' his temper, after becoming involved in a spat with rival coach Jessie J.
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