R2D2Daring Droid Event - Minimum character requirements?

Every legendary event is exactly the same nothing special about R2. If you want 5* you need 5* empire troops you want 6* you need 6* empire troops you want 7* you need 7* empire troops. Not a secret. All legendary events are mostly the same nowadays as far as gearing min for a chance is g8 > much higher chance g9 > guarantee > g10. The one exception to this is I believe GM Yoda and Palpatine as their event hasn't be re-worked to include mods where as all other legendary events assume decent to good mods.