Max Attack Power above 18

Apparently it's not uncommon for chains/shurikens/guns to roll above Max Attack Power 18. I personally have a chain that has Max Attack Power 19 on it right now. I also have a second chain that has Chain Mastery Max Damage 10 on it. I equipped one and screenshotted both reforges next to each other. I've cropped it to make it easier to read the reforge lines but can provide the full shot for both chainblades if you need it for some reason.

max attack power is 1/10001 for 1-18 roll, 1/10001 for 1-20 roll. I don't know why the wiki's never been updated, but yeah.