RTF is a global modification that replaces all towns in the game.

I meant that using a faction with runes to attack with a paw is not a viable option.

It's a perfectly viable option, as proven by the Dwarves. In your example, besides the bears, there was also the rest of the army (and it was too numerous), which should normally be able to defeat these Titans without any losses.

It's just one of a thousand ways to defeat neutral creatures. And the player will find a way to counter it.

If you look at neutral creatures, you might conclude that crossbowmen (armor-piercing shot) are overpowered. And indeed, I used them to conquer almost any guard posts in the first week.

In reality, the difference between having the speed rune and not having it is not very significant, in terms of the chance of it triggering; even without it, the chance is still quite high, "almost guaranteed."