If youre using Ursula, Deceiver of All, to sing song cards costing three or less ink - such as Friends on the Other Side and Bear Necessities - then youll be able to perform their abilities twice in succession, which is possibly game changing
This means that, while Vorinclex and Jin-Gitaxias are both heavy-hitting cards, their tendency to revert back to the front face after the first few turns makes them less reliable
While the effect relating to hit counters is nice (and shuts down graveyard decks), the deathtouch passive is the real attraction
This means you can get two uses out of it, similar to cards with flashback
Ill confess to having tried to build a Kardur deck myself at one point
For end-game options, we likely want both Cinderella - Stouthearted and Tamatoa - So Shiny