The Dog House Megaways: a kennel with a variable floor plan
The original Dog House was a fixed twenty-line machine with a very clear personality. The Megaways conversion throws that structure out and replaces it with reels whose height changes on every single spin. One reel might arrive carrying two symbols, the next might arrive carrying seven, and the number of ways to win is recalculated from scratch before the win evaluation even begins. Some spins hand you a modest little board. Others unfold into a wall of dogs, bones and chew toys with an enormous way-count printed above it.
That variability is the entire point, and it is the first thing you should study in The Dog House Megaways demo above. Do not spin mindlessly. Watch the way-count counter for thirty or forty spins and notice how rarely all the reels come in tall together. The huge boards that make the game look explosive are a minority event, and most of the time you are playing something far smaller than the marketing suggests.
Add the horizontal reel that runs across the top on many Megaways builds and the arithmetic gets wilder still, because it can add symbols to several reels at once. The result is a machine whose shape you genuinely cannot predict from one spin to the next.