See Challenge # 112.

Thinking of other Velorn effects that could go on a black spell, I thought of things "gods" might do to someone. I had a hard time thinking of something appropriate, but thought of the cursed-by-the-gods aspect.

Mechanically, black is borrowing from red and white here, but hopefully it makes a sensible whole. I think this is comparable to pacifism or arrest: it works better on creatures with 2 toughness because they just die, worse on creatures larger than 2/2 because they can still attack, but better on creatures with powerful static abilities because you still have a chance to remove them.

I tried to balance it at a point where the simplest use would be on a 2/2 or less, but it was also worthwhile using it on a larger creature.

I wanted to add something like "when it attacks, its controller loses 2 life" to play up the "aaaaagh!" aspect, but it just made the card too busy. I'd like that on a card where either the "shrink must attack" or "lose life on attack" mode could be activated separately or together.

As of Viper's Kiss, black forestalling activated abilities has a precedent. The "attack each turn if able" feels super red, though.

I think the flavour works to make this feel fairly black. Admittedly the flavour of "mad" is often red: rename it "Fragmented Mind" or something for the same meaning but sounding more black :)