Is there a strategy for tournaments?

Yes, there are strategies and I posted those prior to All Stars 2024. All Stars posts have long since been deleted, but I will add my favourite strategy here:

One important strategy in general is to not overplay in the earlier rounds. Carefully read the Terms and Conditions and look at the info King give us: If they state something like "10/20/30 players per leaderboard" then this means that essentially there will be unlimited numbers of leaderboards. So each time another 10/20/30 players start playing that particular round another leaderboard gets added, and in my experience this means that we can start a 72 hour round just 12 hours from the end. There is no guarantee you will get easier competitors by joining late but it does definitely mean that you will have to crush for a lot of a shorter period of time because you will be matched with other players also starting late. The first benefit is you save time and effort (and sleep), the second benefit is you save levels and probably boosters and gold as well. If you are playing one of the easier level ranges then by using this strategy you will still be on the easier levels when you play the final round, in which you will have to crush non-stop.

King do not generally want us to know how many leaderboards there are and how many players there are on each leaderboard for the really big competitions. So in All Stars 2024 King took us by surprise by making every single round prior to the actual final round unlimited leaderboards. They did not advertise this, but in this community we shared our experiences and one member (not myself, I was on a busy holiday at the time unable to compete) got to the final round practically by accident because they did not start to play the previous (finals 2/3) round until it was almost finished. In All Stars 2023 it had been different, so until the round starts we do not know if it is safe to join late. This is where you need to play the "Call a Friend" joker (as they call it in the Who Wants to be a Millionaire game show): To make sure it is safe to join late in the two rounds just before the actual final (equivalent to "finals rounds 1 and 2" in the Music Tournament) find a friends who also plays: If you know someone else who plays the tournament and who starts to play soon after the round has started they will be able to confirm if their leaderboard fills up after they themselves start (unlimited leaderboards) or if there are already players on the leaderboard when they join the round (limited leaderboards). In the final round leaderboards are always limited to 10, but this may be the only round you really have to play full out for the entire duration. If your friend tells you that they were the first on their leaderboard and it filled up after they started this is a sign that there are unlimited leaderboards and you can save your crushing time by joining much later into the round. That way you can go into the final round refreshed rather than sleep deprived and have a much better chance of winning.

We did share our experiences about which type of leaderboard we encountered and I did post here and advised players about this during All Stars 2024, so my best advice is to stay around in this community and watch out for our posts during the next Big One. We can be our "call a friend" here in the community and will have valuable information and tips to share.

Yeah this was ultimately a marathon + skill competition. There's a natural limit to how many points you can earn per hour, the game only flows so fast. If you weren't willing to play the entirety of the final final round, your chances were diminished.