Not sure about kisame, but kimimaro, guy and hidan are now guaranteed during first 13 seal scrolls in seal treasure (at least thats exactly what i got at the same number of pull on 3 accs)

Those 20 pulls have fixed ninjas in their drop table after certain number of pulls. Honestly, its not a bad idea, since getting 3 3* ninjas right away at lv10 makes early life a lot easier th*ing crap team7. Also 20seals isnt much of an investment.

edit:

found a link where that was already mentioned: https://forum-narutoen.oasgames.com/page/show-post-26615-1.html

Those rares arent fixed, but they appear exactly on set number of pull.

Yes. However, you can propably get a few seals from various sources already, add coupons to that you earn on first days and suddenly it comes to 1k, which is not that much. Also, considering this game's overall pricing(200$+ for a single decent ninja), if some1 aims for the top that ammount of money is pocket change. This game is heavy p2w, the sooner you realize that, the better ;-)

As I said, if someone already is spending- 20 seals is nothing and lets you get ahead and breeze through content (not to mention other players during early pvp). Even for active f2p, thats basically 2~ weeks of grinding seal scrolls. Those ofc shouldnt do that (all those ninjas are free in time), since they usually want to maximize their gains by playing the long game, not a short powerboost. Also you will get ALL 3 rares from that 'feature" over 40days of free draws, but by that time propably all of them will be useless.