After reading this again, I've changed up the final build a tad bit to reflect your ideas. Hope you don't mind!

Honestly, this is by far my favorite build I have seen for any character. I typically substitute Bonesaw with Tornado Trigger unless the other team is carrying loads of armor. I like the extra speed it gives and the added crit chance really helps. I usually substitute Crucible for Fountain of Renewal as well unless the other team is all blue/red. Late game this is an absolute beast build. You are tanky enough to sustain a good amount of damage and if played right, your damage output can wreak havoc on the other team. People don't expect Catherine to be a huge damage dealer so it really throws them off guard when you can hold your own in the damage department. The Boot/Warhorn combo, coupled with Merciless Pursuit allows you to cover almost 3/4 of the lane at high speed. This is absolutely crucial for chasing down low health heroes in late game team fights or ganking from long distance mid/late game. This is now my go to build. Aftershock at the end is negotiable for me as well (if the match even gets that far). Depending on which defensive items the other team is carrying, sometimes I'll add Serpent Mask instead of Aftershock, just to add some extra damage and still maintain a good bit of lifesteal. Thanks for the work on this build!

Honestly, this is by far my favorite build I have seen for any character. I typically substitute Bonesaw with Tornado Trigger unless the other team is carrying loads of armor. I like the extra speed it gives and the added crit chance really helps. I usually substitute Crucible for Fountain of Renewal as well unless the other team is all blue/red. Late game this is an absolute beast build. You are tanky enough to sustain a good amount of damage and if played right, your damage output can wreak havoc on the other team. People don't expect Catherine to be a huge damage dealer so it really throws them off guard when you can hold your own in the damage department. The Boot/Warhorn combo, coupled with Merciless Pursuit allows you to cover almost 3/4 of the lane at high speed. This is absolutely crucial for chasing down low health heroes in late game team fights or ganking from long distance mid/late game. This is now my go to build. Aftershock at the end is negotiable for me as well (if the match even gets that far). Depending on which defensive items the other team is carrying, sometimes I'll add Serpent Mask instead of Aftershock, just to add some extra damage and still maintain a good bit of lifesteal. Thanks for the work on this build!

This is a really interesting build. I like the general discussion of Catherine, as well as the specifics you put in. I'm definitely going to try it.

Bonesaw catherine? Wow...that actually sounds like a pretty good idea!

I like the idea behind this build. You don't see very many WP variations of Catherine. Nice breakdown of the strategy as well. I personally would go with Crucible instead of Fountain only because of the huge boost in health and Reflex Block active, but that's just my preference. With full boots and horn (plus aftershock effects) I found it to be enough health regen. Nice Job!