In your upkeep you gain 2 life on the battlefield or in your Command Zone, so you never need to cast him
and you can also put it on Mirage Mirror for future copying
It also nullifies your opponent's graveyard - pretty backbreaking for strategies like 'Dredge' that rely on the 'yard - and allows you to grab your opponent's best threat from the void and play it free of charge (Okay, at the cost of its own life, but it's a lowly two-drop, so who cares?) Paired with targeted discard cards like the popular Thoughtseize, Dauthi Voidwalker has the potential to be super scary
The ETB damage keeps early boards under control, and if you cast it normally, youre left with a double strike creature that closes games quickly
This might be a better inclusion for a spider deck than a spider commander in its own right
Which cards are you most excited to play with and which deck will they go into