Unique voucher for guest that creates another unique voucher

[Clorofeella]

Hello, i'm looking for something that allows me to generate something like 20.000 unique vouchers with 25% discount (this discounts will be printed and given by hand to the final customer) and then if someone uses this voucher, send by email a second unique voucher with 10% discount

Is possibile to do this only with guest customers?
I don't have registered clients and i don't give the opportunity to register, every order is placed by a guest customer

I thinks there will be a problem with associating the first order with the second order

Thanks

[joseantgv]

You could associate the second voucher by email. But you need custom development for this.