I have a 36kg rollered game rod with a heavy game trolling reel filled with 500m of 100lb dyneema braid. Terminal tackle was 2ft of 200lb nylon coated wire trace with ganged 8/0 stainless hooks.

On full drag (as tight as I could physically get it) this mysterious creature of the deep pulled 180m of line off in less than 20 seconds. I have had some large fish on this rod but nothing like this.

Any ideas on the size of shark (assuming shark because of the speed) that could have done this.

For what it is worth I managed to get a 5 minute fight out of it but is headed into a large group of anchored boats. The anchor chains ended up cutting the line.

Thanks all who respond.