Shattering Blow is surprisingly good these days, and though Lightning Helix is below rate for Commander, it still hits a huge swathe of popular Commanders and setup creatures
Fateful Tempest is so neat
Terrible stats aside, this cards two abilities dont synergize as well as you might hope

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Whats more, the only advantage Duneblast has is that it leaves something in play, so it can be played pre-combat