High-flying Munster survived a fright at the hands of Ulster in a match staged against a Halloween backdrop named the 'Night of the Living Red' to clinch a 32-28 victory.
This was a blink-and-you'll-miss-it affair under the Friday night lights - swirling wind and rain making it compelling viewing with the Thomond Park crowd rewarded and warmed with an eight-try show.
Five different players scored five tries for the hosts for whom scrum-half Tomas O'Leary pulled the strings, deservedly being named man of the match.
Ulster took the advantage when Craig Gilroy touched down for an early score, only for Paddy Jackson's conversion to be swept wide of the target by a strong and swirling wind that created headaches throughout for both sides.
But the hosts were soon level and then ahead, O'Leary's initial break had Ulster frantically back-tracking before a quick offload to James Cronin, who was equally deft releasing Andrew Conway.
Full-back Conway turned on the burners to brush aside flailing tackles, touching down for an 16th minute try that Ian Keatley duly covered.
However, within two minutes Jackson had threaded a penalty in front of the posts to put the visitors back in front.
And they extended that lead further when Gilroy added his second, finding himself alone and in space on the wing and crashing over from short range, Jackson missing the extras to keep the scoreline close and the atmosphere edgy.
Robin Copeland looked in pain after a heavy tackle in the build-up to Munster's first try but he was soon back on his feet to reduce arrears with a score of his own, neatly combining with Simon Zebo and Keatley, who also added the extras.
It was a try that seemed to inspire the hosts and three minutes later they scored again, Gerhard van den Heever making a break and backing himself to go alone for a try that the previously unerring Keatley failed to convert.
Ulster scored their third - reducing the half-time score to 19-18 - winning a line-out and then taking control of a maul, Nick Williams showing predatory instincts to cross the line and Jackson hitting the post with the conversion.
Rarely has half-time been as badly needed to catch a breath while the arrival of torrential rain didn't make it any easier.
Jackson edged the visitors ahead with a drop goal - a brave tactical choice in the swirling wind - but Keatley kept his nerve, restoring the hosts' one point advantage with a well-stuck penalty as Ulster were penalised again at the breakdown.
Advantage was swinging one way and then the other and Denis Hurley's score, following sterling work by van den Heever and Conway, was awarded after the TMO had been consulted.
The hosts scored their fifth when winger Zebo muscled over, though Keatley's missed conversion meant Ulster were still close enough to make it tense.
They got even closer - just five points - when Dan Tuohy scored and Jackson converted but the hosts held on to deliver maximum points in a thrilling encounter.
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