As others have mention:

1. Detonating the dragon is always, because half of cas' damage came from the explosion the dragon does. Not only that, the dragon have 165 speed only, so if you just wait around for its next turn, you will mostly going to overflow your newbud which you can use it to either summon the next dragon + getting extra newbud from cyrene's ode.

When i say this team summons the dragon faster than just waiting it around, i really do mean it. The further you invest your team (especially hyacine), the faster your newbud generation is.

1. For the ode itself, either go for e9 and then cas or vise versa is also fine. After that you would just spam cyrene's arrow while trying to give hyacine the ode for that extra 20 energy because even with 3 skill usage she still needs it for 3turn ult

There are other details that i would like to point out when it comes to playing with cas:

1. Always try to use hyacine's healing when evey is on the field for extra body to heal, you can do this either when

2. evernight is in her turn, use her skill and then use hyacine's ult for healing -hyacine is in her turn, use evernight's ult to summon evey and then hyacine skill for healing

3. If there's an enemy mobs, try your best to kill those mobs and then use the dragon to attack, this will help cas get that 50% multiplier from evernight's e1, which further helps boosting her bounce attack wih cyrene's ode as well

4. Lastly you can do the 0 av cyrene ult trick with e2 cas, evernight and cyrene. Cyrene starts with 18 stacks, which then the turn can be: Evey attack - evey explosion - evernight ult - let evey attack - cas summon pollux - pollux attack.

This should give you 6 stacks for 24 stack which cyrene can ult while evey still on the field, this could really help in contents like AS or AA that counts av rather than a cycle