In the ruling about Wall of Roots is written the following:
2017-11-17: If you must sacrifice a creature to pay a casting or activation cost that also includes mana, such as that of Bubbling Cauldron’s abilities, you may put a -0/-1 counter on Wall of Roots to make its toughness 0 and then sacrifice it to pay that cost.
I do not understand this properly. Compared to the state based actions this seems wrong. You would get the mana and then the creature dies. Mana ability are for normal not using the stack, and can’t be responded to. But this is a mana ability, and a ‘put a counter on a creature ability’. Does that mean, that the ‘put the counter ability’ is still on the stack, when you already got the mana? A creature can’t have toughness 0 and then become sacrificed.
I hope someone can explain to me this strange card.