The effect of Untimely Malfunction's last mode won't cause creatures that are already blocking to stop blocking
If I were struggling to find drafters, I would try asking if anyone is playing MTG these days and looking to draft at my local store on the Orlando subreddit
The first loves to recite the flavor text to Fodder Cannon whenever given the chance, the second has his Weatherlight Crew deck, and the third has read and remembers the characters from every Magic novel ever printed
If youre intent on cheating costs, then Isshin might be good alongside cards like Winota, Joiner of Forces, or within a Kaalia of the Vast deck
You can give a creature you plan to sacrifice a regeneration shield, it just wont do anything since regeneration only protects from lethal damage or destruction
Attacking into them isn't fun, and I believe defenders can be more powerful in Oathbreaker than spot removal