Doing a recap about Rurouni Kenshin Collab which happened a while back in Japan version and had also reach the other regions if I'm not mistaken. I did a single roll and was very lucky to get Saito: http://www.puzzledragonx.com/en/monster.asp?n=3033.
He was my first orb cross leader and I had quite a bit of fun with this new playstyle. I also did not buy You-yu and he was a decent replacement for a leader with insane attack multiplier. (Not sure if UUVO Sarasvati arrived at that time though) Saito should be very useful against the +297 Zeus dungeon although I have not tried him yet. I have some friends who put him up for a while but everyone had eventually moved on to other leaders like the heart-crossed ones which are just better overall. I hardly use him now although my dark box had the most +297 cards and it's mainly due to my blue cards slowly becoming better after the Summer Gacha and also a certain Blue Miru... I'll talk about that gacha in a future post soon as I continue my recap.
The other card I kept from the Collab was Anji from the dungeon: http://www.puzzledragonx.com/en/monster.asp?n=3045. I kept 2 in fact as I managed to max skilled 2 while farming Saito's skill-up card at the same time. I use one of him occasionally in my Red Odin button-press teams for quick Guerrilla Dungeon farming. I didn't get around to fully awakening the other Anji but once done, I can do a team with 5 button-press nukes using them, Awoken Ra and the 2 leader Red Odins. Rounding up the team with a Tengu and the skill boost badge, I'll be able to have all nukes ready on turn 1.