How to make J4 and Anivia relevant in light of the mobility creep

####First, some background:

and used to be strong picks, because they could create terrain which can turn the tide of a team fight. This was true because not many champs had dashes, so J4's ult really locked up anyone in it, and Anivia's wall was actually a movement impediment.

However, with the slew of recent champs who have gotten dashes (dubbed, "the mobility creep"), these abilities have become less relevant.

####Second, some perspective:

You might be wondering, "If temporary terrain has become weaker, why is still relevant?"
The answer is twofold:

1. Secondary CC: Trundle's pillar also slows, even if it gets dashed over.
2. Cooldown: Trundle's max rank pillar is on an 11 second CD (6.6 wth 40% cdr) and lasts for 6 seconds. With his frozen domain, he can easily stay in range of a fleeing target to land his second pillar.

####Third, some short analysis:

The real problem with Jarvan and Anivia's walls isn't that they can't contain people, it's that they don't really have too much of a negative effect on their opponent (assuming the opponent has a dash): the opponent uses said dash, and continues going about their merry way (ie, doing whatever they were doing before; there's no reason NOT to go over the wall).
For contrast, when trundle pillars, you have to think: Do I want to use my dash now, or try to wait out this pillar so I can dash out of the next one? You never have to think, "Am I sure I want to dash out of cataclysm?"

####Fourth, a simple solution:

There needs to be a reason not to use your dash to go over the wall or out of the cataclysm, the same decision you make when you think, "Do I really want to dash through trundle's pillar?"

I think either a being slowed or taking damage for dashing through temporary terrain would be an appropriate consequence.

Thoughts?

######Finally, I must give credit where credit is due: Though the analysis is mine, the original idea is CommanderMath's, in this comment.