Speculation for tomorrows gyarados and magikarp event, what to expect?

The data miners leaked almost the full roadmap for this year and we know what’s coming, but it seems tomorrow we get a gyarados magikarp event and the dataminders don’t even know what it exactly is or what the rewards look like.

it’s either like the meowth chansey event with wonder picks or similar to the Lapras event where we get to fight the CPU.

but why magikarp and gyarados ? Do we get a promo card for these, for example a red gyarados? Is there a Gyarados EX coming just like Lapras and we don’t know anything about it yet?