The Lions will come up against the haka for the first time on their New Zealand tour when they face the Maori in Hamilton on Saturday.
But how will they respond to the traditional war cry?
BBC Sport pundits Martin Bayfield and Zinzan Brooke give their insight into what it means to those on either side of the haka.
I didn't play in the New Zealand Maori game during the 1993 tour, I was in the stands watching it.
You need something to inspire - the haka does exactly that
But even from there I knew this was something special for the Maoris when they lined up to do the haka.
It's part of rugby folklore and each team has a different approach on how to face up to it.
The first time I faced up to the haka was for the Lions during the first Test in Christchurch in 1993.
It suddenly dawned on me I was playing a part in rugby history - facing the All Blacks for the Lions is something incredibly special.
And believe it or not, I didn't find the haka intimidating at all. In fact I found it motivational.
It's the same as lining up for the national anthems and hearing Land of my Fathers sung with so much passion by the Welsh or the French singing La Marseillaise.
There's nothing like hearing those anthems sung with so much gusto, it literally lifts you.
You need something to inspire - the haka does exactly that.
On this tour the intensity is going to be raised several notches.
The crowd are going to go absolutely crazy when the All Blacks take their place for the haka in Christchurch on 25 June.
And I cannot wait.
The Maori do exactly the same haka as the All Blacks, but when I was playing for both we practised it more with the Maori.
I knew when I could see fear in a guy's eyes
The Maoris should know how to do it better than the other guys - it is all about the passion and tradition of the culture.
You have to make sure you do it right and, having looked at some of the archives from 20 years ago, there is no comparison with the ones today, which are a lot more 'follow the leader'.
The leader is always one of the most senior or experienced Maori players.
It is a war dance, a war cry, and I'd imagine it is intimidating if you come right up against it a few yards away.
You can see the opposition's blood vessels pumping and the veins popping.
I knew when I could see fear in a guy's eyes and sometimes they just had to stand there and take it. That felt fantastic.
Every opponent treats the haka differently but that never bothered us.
Mentally, the opposition need to respond, because I reckon it gives you a little edge in the first five or 10 minutes.
David Campese always used to run off and do his own thing. The old Wallaby hooker Phil Kearns used to stand there and smile, and give you a wink if you looked at him.
The England hooker Richard Cockerill came right up in front of our faces and challenged us, which was interesting.
I remember the big Irishman Willie Anderson marching the whole side forward in front of us which really got the crowd going.
It is all part of the ritual.