If you discard a card while a spell or ability is resolving, the triggered ability resolves after you've finished resolving that spell or ability
Spells and abilities that were targeting that permanent and Auras and Equipment that were attached to that permanent aren't affected unless the new characteristics of the object change the legality of those targets or attachments
In this list, well primarily be looking at cards from a Commanders perspective
The creature lands from Battle for Zendikar block, which enter tapped and have activated abilities that make them creatures until end of turn
Bloodroot Apothecary has toxic as well, so if it connects, this makes it so your opponent can sacrifice even fewer tokens as it gives the same amount of poison counters as its ability does
Until end of combat, you dont lose this mana as steps end