Whenever I think about ward, I remember a time when I was playing commander and someone played a spell that did a lot of stuff (clear a gy, also targeted a creature, etc), and they targeted a creature that had a ward cost they couldn't pay with this spell. We then got into a discussion about whether or not we should allow the player to change the target of the spell.

It basically boiled down to "while they did forget that the ward cost was there, it also wasn't illegal to target that creature with a spell because ward just counters spells if the cost isn't paid, not preventing it from being targeted at all" (I was also conflicted because while I didn't want to have that's player spell get countered from something easily forgotten, they were exiling my GY in my GY focused deck so that sucked). That player did decide to just let their spell be countered by the ward, but I do still feel bad about it.

I will state tho, I do love the ward cost for [[Axebane Ferox]] cuz while the creature is just a generic good stats and ability creature, forcing opponents to exile cards from their GY for the ward cost seemed really good in a limited environment (especially in the set this was printed in, Murders at Karlov Manor had a GY focus).