The goal here is to avoid rule 509.1b

> The defending player checks each creature he or she controls to see whether it’s affected by any restrictions (effects that say a creature can’t block, or that it can’t block unless some condition is met). If any restrictions are being disobeyed, the declaration of blockers is illegal.

> A restriction may be created by an evasion ability (a static ability an attacking creature has that restricts what can block it). If an attacking creature gains or loses an evasion ability after a legal block has been declared, it doesn’t affect that block. Different evasion abilities are cumulative.

If it works that way; this is gonna be incredibly confusing.

Perhaps simpler to understand would be something like: ­: Target attacking creature is blocked, and fights ~.

I've seen related designs before, and I like them, and I'm not sure if the simplest way. Maybe an activated ability which says this blocks target creature with reminder text that it ignores evasion? I've also seen "this creature can block any creature as though it had no abilities" but I'm not sure that works

Something that definitely works:

Green Wall
­
Creature - Wall
Defender
Green Wall can't block.
­: Target creature attacking you or a planeswalker you control becomes blocked by Green Wall. (This ability works on creatures that can't be blocked.)
0/5

There's a little bit of precedent with Trap Runner. I should point out that this doesn't work with hexproof creatures but... I don't see that as being a problem. That's kind of the point of hexproof.

Also, you can remove the line about Green Wall not being able to block creatures. That's there to prevent the Wall from double-blocking. But maybe double-blocking is fine.

You could instead of saying "can't block" with jmg's suggestion put in a timing restriction, "activate this ability before the declare blockers step."

The reminder text and that rules text don't fit like this. Since "can't" trumps "can" an ability that uses "can" cannot overrule a restriction (which by definition uses "can't").

You could however have rules text that lift the restrictions specifically by ignoring individual or all restrictions - which means this card blocks as though there are no restrictions (though there would be weird questions to be considered e. g. regarding Silent Arbiter and Mirri, Weatherlight Duelist with multiple of these).

My favorite way to word this ability was "~ may block as though no other permanent has abilities." but that doesn't cover already existing continuous effects of triggered/activated abilities.

Read the current text and reminder text of Trap Runner. Sounded counter-intuitive to me too, but it evidently works.

­Trap Runner has an activated ability (: Target unblocked attacking creature becomes blocked. Activate this ability only during combat after blockers are declared. (This ability works on creatures that can't be blocked.)) - Green Wall has a static ability (Green Wall can block any one creature. (It’s not affected by any restrictions during Declare Blockers Step.)). Those are entirely different concepts.

Doing this with an activated ability or triggered ability that just changes the state of creatures is different from using the game action of blocking - since that is specifically synonymous to declaring a blocker.

Quite intuitive really.

Your logic would also catch Trap Runner. Creatures that can't be blocked can't be blocked. It doesn't matter whether they are blocked by a creature, or are just 'blocked'. It can't happen.

But Trap Runner gets around that. It does it by ignoring the step where the creature would be blocked, and instead says that it has become blocked.

Likewise, if you say that a creature is being blocked by Green Wall, you've also stepped around the fact that Green Wall can't block. The evasive ability doesn't matter because blocking is already happening. It's not a static effect like like Archetype of Courage. In fact, look at how Archtype is written, "Creatures your opponent controls lose first strike, and can't gain or have first strike." That's a lot of qualifiers ('lose', 'can't gain', 'can't have') Wizards doesn't just add extra words for no reason; they are there to cover every corner case. For activated Green Wall to not work, the reminder text for flying would have to read (This creature can't be blocked, and is not blocked except by creatures with flying or reach.)

Well, "activated Green Wall" would work, but I'm looking to the left and see that Green Wall has no activated ability. Are you claiming that's a display issue?

I already cited the card text that I'm seeing to you, so it should be obvious that I'm not refering to anything but the card as of its most recent update made by kauefr.

p.s.: Also your flying reminder text example is still incorrect since it should use an inchoative phrase over a phrase of state ("become blocked" over "is blocked").

Ah. The timing of your comment made it look like you were drawing a difference between Trap Runner and my suggestion. My apologies.