Tropical Tidal Wave is a very hard to obtain Trainer since its a reward card for worlds. The effect is, quite frankly, mediocre and makes
Pokeball look good by comparison. The effect certainly has its uses: on heads you take out all Trainer cards your opponent has in play. That can be really powerful, though not so much in the current format (sounds like that will change soon). Even in a format where many of the various "stays in play" Trainers are common, I'd think the "tails
backfires" would be a serious turn off. Some decks will turn it to their advantage, of course.
I guess what I don't like is that when the metagame doesn't use a lot of Trainers that remain in play, the effects is
underwhelming. If we had a format not unlike Unlimited was for several years, where you expect almost every Pokemon in play to have a Tool, and players to be jockeying for Stadium control, then it seems
overwhelming. Quite a Yu-Gi-Oh vibe, really: time it right it will act like a "tails fails" effect, namely when you have nothing you want to keep in play!
So why would I rather use
Pokeball? Well in the current format, it's just more likely to be useful, and the reason for the comparison is "tails fails" of
Pokeball versus "tails backfires" of
Tropical Tidal Wave.
At the not-so-subtle prodding of Waynegg, I will add that this is a nice collector's piece. To bad I only know it says "Worlds 10" on it and thus pertains to Pokemon World Champions 2010 and not the exact circumstances (e.g. how many people got it), but claims on this thread are that it goes for a decent hunk of change. It also appeals to those who enjoy images of the Pokemon on it, including
Surfing Pikachu. There are a few promos (only the art is different on them) featuring
Surfing Pikachu. I don't know which came first, but there is the TCG card, the ability to earn a Pikachu that knows Surf in the video games in Pokemon Yellow, and a Pokemon episode that features another Trainer whose Pikachu does indeed surf! Plus scenes with multiple Pokemon on it, especially doing something not related to battling, is quite pleasing to some fans.
Ratings
Unlimited: 1/10 - Only because it has a greater potential to backfire (since you're as likely as your opponent to have several Trainers in play) and faces almost certain Trainer denial by the time there are enough viable targets even if you're not in a "goes-first-wins" kind of metagame.
Modified: 2/10 - Nothing really good to target right now.
Limited: N/A - Plus given the scarcity of Trainer cards on top of this only hitting what stays in play, what are the odds it'd actually do anything with either result?
Art: 7/10 - Not bad, but nothing special to me. Apparently I am in a minority.
I have to score it higher than I would (and did before editing this post) since it
does do things pleasing to several various fan groups.
Summary
A great card for collecting, but not especially useful for play unless there is a dramatic shift in the card pool and metagame.
