Because his name is silly.
But in all honesty, I'm glad they're doing the top 2 of each. While I prefer Lyn, I also really like Lucina, so I was prepared to be happy with the result either way. Now they're both there! Let's just hope they aren't all red units and can be diversified from their normal forms a bit. I know Ike could go green and Lyn go transparent, but not sure what Roy and Lucina could do. Guess Lucina could go blue?