Thwart the grave is quite exciting. Potential double reanimation for 6 is still decent, and you're getting a sweet deal if it's less. Very cool art too! Reminds me of something that would fit in with Kamigawa.
Deadly Alliance is a very cool Common. In an average board, it should probably be powerlevel-wise a worse Eat to Extinction or a better Murder, but it could also cost 1B or even B and at that point it's just insane.
Ravager's Mace is really unexciting. If that's the powerlevel to expect from this set's Equipments, sorry but Nahiri is already on a trip to dollar bin town.
Thwart the Grave has absolutely fantastic art. The card ain't half bad either - kinda like a weird but probably better Ever After - and could see play in some EDH or even zany Standard brews.
Deadly alliance is limited necessity at 5 (compare with the bad removal we often shuffle up), playable for 4 - a good deal at 3 (compare murder), and we would actually play it meta depending at 2 mana in standard. If you have it at 1 mana reliably, it would be amazing (fatal push on steroids). If you call a common card that has that range boring, your expectations for a common are out of whack.
Thwart the grave is amazing. Compare to victimize ever after - I see this as having a decent amount of commander play and I could envision a situation where this is 1BB reanimate 2 critters in standard even.