Yo! When I got to that part in the stage, I noticed three things. 1) It was underwater. 2) The walruses on the top and bottom which I noted from previous encounters that they produce unbreakable ice chunks. 3) The single line of rings going between the two rows of walruses. To me, it was pretty damn obvious that they wanted me to go full speed with Submarine-Tails through them all. Does that excuse the fact that they made it unescapeable, or heck, ANY of the typical DIMPS "botomless pit at the end of a level" bullshit? Not really, but if you payed attention to the level ahead of you, you shouldn't have had trouble with it.