I've been thinking I need a different mechanic for the Black Knights faction. Overthrow didn't play very well. I particularly want it to play into the set's "mind games, tactical genius" feeling.

So my current plan is: Some Black Knights cards will have Raid abilities. They reward you for attacking. Other Black Knights cards will have Revolt abilities. They reward you for having your creatures die. Both of these are reprint mechanics (Mardu Heart-Piercer, Lifecraft Cavalry), but the flavour of the names "Raid" and "Revolt" is perfect for the set, and I think the gameplay will be a good fit as well.

The result of having both of these in the set should be: I attack you with a 1/2 when you have a 2/3. Do you block? The possibilities are:

1. I have a Raid card in hand. I've already got my benefit; it's safe for you to block.
2. I have a Revolt card in hand. I'm hoping you block and kill my guy. You shouldn't.
3. I have a combat trick in hand. I'm hoping you block so I can kill your guy. You shouldn't.
4. I have a saboteur effect in hand. I'm hoping you don't block so I can use my saboteur trick. You should block.
5. I have none of the above and I'm just bluffing. You should block.
   (6. I have multiple of the above, and can perform a magnificent Batman Gambit whichever way you react. Muwhahahaha!)

In order to stop this being completely random and unpredictable, I'm planning to have the distribution of these abilities spread around different colours. Flavour-wise, I think it works for green to get Revolt - the traditionalist Japanese faction are green, and they want to return to their old traditional ways, but to do that they need to overthrow the Britannian oppressors. And I think Raid could happily go in any other colour, but most likely black - the more ruthless Britannian elements and assorted self-interested vigilante groups conduct various raids on each other too.

My thinking is that, across all rarities, the distribution will be something like:

Raid: 5 red, 4 black, something like:
1-drop . 2-drop , . 3-drop , . 4-drop , . 5-drop . 6-drop .

Revolt: 5 red, 4 green, something like:
1-drop , . 2-drop , . 3-drop . 4-drop . 5-drop . 6-drop , .

The set will also have a good collection of saboteur effects to make it riskier to not block. Mostly these will be visible on the card, like Scroll Thief, Centaur Rootcaster, Blind Zealot; but there will be some cards, blue in particular, that can grant saboteur effects at instant speed - such as Prepare for Infiltration, and in which category I'd also count Ninja in Disguise.

Combat tricks will be in all colours but focused in green and red. So against a green-white deck, you shouldn't block; against a blue-black deck, you should block; and if my colours include red, all bets are off. (But if I only have one mana up, then the red 1-drop revolt card might be rare, so it's not very likely I have it... and so on.)

I'm not sure the whole thing will be feel-good. It's like that pair of morphs; one did nasty things when it hit you, the other did nasty things when blocked. With the same morph cost. Should you block or not? No way to know. Play randomly and feel bad.

This pair of mechanics could come out the same way, if you're not careful.

But they do seem like a nice flavour match.

That's what I was going for with my "In order to stop this being completely random and unpredictable, I'm planning to have the distribution of these abilities spread around different colours" and "So against a green-white deck, you shouldn't block; against a blue-black deck, you should block; and if my colours include red, all bets are off. (But if I only have one mana up, then the red 1-drop revolt card might be rare, so it's not very likely I have it... and so on.)"

I'll definitely have to keep an eye on it.