Hi Danish,
Thank you for contacting community support.
The functionality you are looking for can be achieved with an Workflow or a plugin.
Regarding the logic behind it, what I'm thinking is the following:
-for workflow you can trigger an workflow on the update of the case owner in order to send based on certain conditions an email to Tier 1, 2 or 3
- in plugin you have a lot more to work with, you will have to trigger a plugin on ideally post-operation for the case update owner where you will define your own logic, however what you need to keep in mind, ideally I will recommend plugin for this scenario because you have more control, you can add a certain text for each team, you can perform send actions and so on.
Thank you for using Microsoft Dynamics 365 Communities,
Dynamics CRM Support Blog
Madalina Toma
Support Engineer
Microsoft Dynamics 365