ま まけた…………………………!
I-I lost!
へへ…うどいかにくん! つよくなったね…ぼくの
かんぱいだ! それじゃ やくそくどおり
ぼくの しょうたいをみせるよ………………!
Heh heh...Udoikani! You've grown strong...I tip my hat to you! Well then, as promised, I'll show you my true form...!
へへ! じつは ぼくだったのさ!
まぼろしのていおう なんて このよには いない!
そのなのとおり すべては まぼろし…
Heh heh! Actually, it was me! There's no such thing as the "Illusionary Emperor"! Just as the name suggests, it was all an "illusion"...
あたらしい らいばるを みつけるために
ぼくが しくんだ おしばい だったのさ!
ごめんよ…さいごまでかくしてて…でも
It was an act I devised in order to find a new rival! Sorry for keeping it secret to the end...But...
きみならきっと ここまでこれると しんじていたさ!
そして みごとに ぼくのきたいに こたえてくれた!
ありがとう!
I believed YOU would be able to make it all the way here! And you've met my expectations wonderfully! Thank you!
せかいじゅうには おいらたちよりも もっともっと
つよい ぎゃんぶらーがいるはず…だから
おいらのちょうせんは これからもつづくのさ! ……
There must be gamblers far, far stronger than us out there in the world...So from now on, my challenge continues!...
Yeah, nothing particularly informative there, though it suggests this guy is the main character's gambling rival/friend/friendly rival. This was originally a licensed game based on some manga, right? Presumably you're supposed to know who he is already. Obviously I haven't read it, so I'm afraid I can't help you there.