The mechanic is pretty simple
Unfortunately you lose all of your progress if Hallar dies or otherwise leaves play, and that fact that you want to kick all of your spells plays merry havoc with the mana curve of any deck that has Hallar at the helm
For reference, this cards original printing was in the Strixhaven Commander deck for Osgir, the Reconstructor, who can make multiple copies of this that can be sacrificed when necessary for a brand new hand of seven cards
Sure, the Deathtouch will make opponents think twice about blocking, but this card will still get blocked more often than not
Conduit of Emrakul Conduit of Storms Dronepack Kindred Erupting Dreadwolf Fibrous Entangler Howling Chorus Kessig Prowler Shrill Howler Sinuous Predator Smoldering Werewolf Tangleclaw Werewolf Ulrich of the Krallenhorde Ulrich, Uncontested Alpha Ulvenwald Abomination Ulvenwald Captive Vildin-Pack Outcast
Tolkien wrote, the journey doesn't end here