Hi @jadebiscuit 

Thanks for posting your question in the community!

While I love the idea to dynamically show different content blocks based on the product purchased. 

I have used this resource a TON to set up dynamic show/hide blocks based on event metrics:

https://help.klaviyo.com/hc/en-us/articles/115002779071-About-Using-Event-Variables-to-Personalize-Flows

With that said, setting up an email with 20 different blocks might cause more headaches. I’ve set up a few emails using dynamic blocks and have tried to limit those emails to 2-3 blocks max. 

A couple of reasons:

• One, as you noted, the more blocks you have with dynamic logic, the higher the likelihood something could get incorrectly shown.
• Two, when the email is sent, the code for the email will contain all 20 blocks, even if they are hidden, which could exceed some size limits at the top ISPs (Gmail = 102KB) and the email will be clipped. 
• Third, you do lose the analytics to track and monitor engagement-per product-that might be helpful for future marketing opportunities. 

Based on these 3 things, I might recommend creating an email for each product and either setting up a flow conditionally filters users to the right message, or set up a flow per product and the trigger filters to that specific product SKU or title. 

I hope this is helpful. 

@In the Inbox