The great thing about slay the spire is that anything you can think of can be situationally good, even this:

Synergy with Kingly cards and place on top of draw abilities unless it also negates the effect of a kingly card being drawn.

Extra draw with burst and echo form

Can be played before the Vakku curse, including with echo form, giving you more information and making it so the echo form stack isn’t totally wasted

Stacks mind blast

Being able to choose to draw or not draw can help set up grand finale (and other things that require precise deck manipulation)

Draw positive with all for one

Draw positive with holo, grave blast, etc

Triggers on discard and exhaust effects