When the Mariners moved Casey Legumina to the Rays, the first reaction was pretty simple: of course it was Tampa Bay. When the Rays get involved with a live arm, every fanbase immediately wonders what they have up their sleeve. Legumina had just been designated for assignment by Seattle, so this wasn’t a huge deal. Still, sending any pitcher with even a sliver of intrigue to Tampa Bay always feels like handing a mystery box to the one organization that knows exactly where the hidden compartment is. Now we know what the Mariners got back. And honestly, it makes the whole thing a lot more interesting. Seattle reacquired right-hander Ty Cummings from the Rays, turning the Legumina move into a reunion with a pitcher the organization already knew well. Cummings was Seattle’s seventh-round pick in the 2023 MLB Draft, then became the player to be named later sent to Tampa Bay in the Randy Arozarena trade. Less than two years later, he’s back in the Mariners’ system and assigned to Double-A Arkansas.…