Chaos structures.

The bonus from the Runner is 50%. Plus, it ignores penalties, so it's actually much more.

By the way, somewhere in the thread there are some simple but very interesting calculations – a comparison of Runner + Charge with Runner + Hydra. So, the latter loses in movement speed by almost twice as much when having a full Runner set – boots + quiver (and even gloves). A similar picture will emerge when comparing Nightmares with Iframes, and the higher the movement speed modifier, the more Nightmares will lose to Iframes (this applies to any creatures).