Scarecrow Build Possibilities

Is this an extremely unnecessary conversation? Yes, yes it is. However, I think sometimes roleolay can be just as fun as min/maxing, and even more so it you can optimize it.

Scarecrow as a Great Old One Warlock for Mortal Reminder, Fighter Champion, and Assassin Rogue, all to maximize the surprise mechanic, poison spray, and all other toxic adjecent gas attacks to give the impression of fear toxin with crits. This is an off the top of my head build since I don't even know if Champion affects cantrips. Probably super inefficient.

Thinking about it more, GOO Warlock is necessary, but I think Bard for cutting words would also be a good pick as well as access to Dissonant Whispers, Phantasmal Killer, and other fear based spells. It would certainly be a lot stronger, plus hold person to get more reliable crits. I vaguely remember Phantasmal Killer being more reliable with the mental fatigue status effect which ensures that it always hits and deals really good damage. Crown of Madness, Confusion, Hex, and even Wrathful Smite(Which I don't think Bard can get), are also good spells. I think this build also gets some flexibility if we're talking about Injustice Scarecrow who can fight if we're using a war pick/Sickle.

I'm probably forgetting a class that would be a good match, but thats so far the only sort of build I can think of at this moment that would actually be decent while still playing into the themes of the character. Unfortunately Poison/toxic spells are just so useless since most enemies are resistant or immune.