If a Beast-Warrior monster(s) is Normal or Special Summoned to your field while this card is in your GY: You can add this card to your hand, then immediately after this effect resolves, you can Tribute Summon this card face-up, and if you do, it gains 500 ATK, also banish it when it leaves the field
"Final Countdown" was and still is limited for quite some time at this point, which makes your chances of drawing it in the starting hand rather slim
Likewise, Dark Ruler No More makes a second Stucture Deck appearance, but currently doesn't do enough to take care of high level combo decks ending on Scythe
It also carries huge nostalgia because Black Luster Soldier is already one of the classic Yu-Gi-Oh
Thus another card has to be discarded after fetching Shaddoll Schism with El Shaddoll Apkallone effect
Dragon Capture Jar is nowhere near that strong it only forces Dragons to Defense Position