If you own the following cards, you will have a much easier time with the new missions than if you do not own these cards. Some of them are obvious (i.e. Dracorex), and some of them are not Gold-buyable (i.e. Monarch), but these cards are extremely useful for Missions 230-252. I am not going to list cards that you almost certainly own (i.e., Aegis or Acropolis) unless you will want a lot of them (i.e., eight Sabre).
(If you are still working on other missions and raids, then ignore this post.)
Extremely useful cards for the Occupation missions (230-252)
1. Dracorex
2. Egg Infector (at least two, but four is best)
3. Eviscerator
4. Halcyon the Corrupt
5. Hydra #5
6. Lance Rider #5
7. Lightning Strider
8. Longshot (Is anyone done with Mission 229 but without Longshot?)
9. Lord Halcyon
10. Marrow Aileron (will be in the Promo Vault)
11. Monarch #2
12. Rapier (three is best, will be in the Promo Vault)
13. Sabre #8
14. Zarak (one is enough; two is unnecessary for the missions)
Convenient for a few missions, but you can probably work around them
1. Beetle Bomber
2. Blood Wraith
3. Jixi’rath
4. Metalworks #2
5. Shuddering Keep
6. Tesla Cannon #2
7. Undertaker