CSM: Word Bearers: Best Uses for Malevolent Covenant?

It feels great to say that for all the years I've been into 40k, it seems like the time to play Word Bearers is now. I'm not really into complaining a ton about the lack of parity between loyalists and chaos, and the strength of the Word Bearers legion trait. All this is a well-beaten horse.

Malevolent Covenant gives us the opportunity to guarantee a psychic power goes through if the initial attempt is failed, at the cost of 1 CP and 1 mortal wound.

What are some of the best uses you can think of? Warp Time, Prescience, Death Hex, some of the Malefic powers... the ability to cast a power guaranteed can really define a playstyle, to a certain degree.

As for "sure thing" I guess Death Hexing the target of Slaanesh Obliterators would just smash, but that's such an obvious application.

What about the psyker? Foot sorc for buffing a gunline? Terminator sorc for deep striking and eating an extra wound?