Return that card and the sacrificed card to the battlefield under your control at the beginning of your next upkeep
The second level is also very strong, giving one of your attacking creatures +1/+0 and trample when it attacks
Commander Legal/GC Pauper Not Legal Oathbreaker Legal Penny Not Legal On the Commander Game Changer list (view all) Toolbox Notes and Rules Information for Necropotence: If a discarded card isn't put into your graveyard (due to an effect such as that of Obstinate Baloth) or leaves your graveyard (perhaps because another effect returned it to your hand), it won't be exiled
While the rule side of battles is extremely complex, client presentation is where the type of work we must do fundamentally changes
Ultimately, for now, were just going to have to wait and see what gets announced in the future
That will end up with it casting itself, not on turn three as you might expect, but actually on turn four