Mulldrifter + Venser, the Sojorner

[serracollector]

If I evoke Mulldrifter, when it comes into play, can I respond with Venser, and RFG him before sacrificing him? 

Can you bounce, sac, or do anything to Mulldrifter in response when it hits play with instants or other efx?

Thanks.

[Delha]

The sacrifice is a triggered ability, so yes, you can respond while it is on the stack.

Note that this does not allow you to use sorceries (or comparable effects, such as planeswalker abilities), since those are only playable when the stack is empty.

[AmbivalentDuck]

The only "exceptions" are replacement abilities.  You can't respond to "if ____ would come into play instead ____"  Two present examples are Scorched Ruins and Lotus Vale.

[psly4mne]

If you're talking about the planeswalker Venser, remember that planeswalkers' abilities can only be activated when you could play a sorcery, so you can't respond to the Mulldrifter trigger with his ability.