ADU Automatic Discounts & Upsells app allows users to create a "link" with specific Shopify Discounts; allowing users to drive traffic or sales through a link promotion.

Features:

ADU Links
Shopify Discounts

ADU Links + Shopify Discount Code

Links with Shopify Discounts + Prefill Cart Option

Does ADU always use a Draft order to prepare a checkout?

Have a Discount Code?' Field in General Settings vs. Button on Theme Integration

Replace checkout button's default behavior with a Custom Script

Can retail prices be discounted alongside existing sales in Shopify?