Hi @mthacker - you can definitely setup a coupon code to discount these tickets for both events, but I don’t think you can automatically control that the coupon isn’t redeemed with both specific events in the order. Essentially, in each order you are looking to force a minimum number of tickets across multiple specific events and also check the ticket count for each event against the other. I think this would need a plugin.
There are a couple of options without a plugin though. You could set this particular promotion to only work over the phone rather than the internet and your staff can control the usage. This is probably the simplest option.
You could let the coupons work online and setup a workflow notification to alert your staff when a new sale comes through using the coupon promotions. This would let your staff keep an eye on these web sales and contact patrons after the sale if they need more or different tickets to qualify for the discount. (Putting explicit instructions in the external coupon notes with html links to add tickets to each specific event may help make it easier for your patrons to process themselves correctly.)
Depending on the use case, I suppose that you could also setup a placeholder event where 1 ticket is the combined $20 price and then your staff can manually book the correct tickets for the real events. While fun to brainstorm, though, this solution seems extreme for most bundling needs
Hope that helps - I know there are other users who’ve made promotional bundles and who may have different feedback!