Actually subverters can disable structures. At least their abilities. They are very good against vasari hangars with phasic trap upgrade......
Heh, well, I stand corrected on that one. Good to know, though if you've got a substantial number of combat units and can get them safely in range of a structure you may as well just blast it.
at least the enemy ai is stuck on his homeworld unable to attack.
Then take your time and experiment a bit. When I first got the Entrenchment expansion pack, I reloaded my assaults against starbases repeatedly to try different approaches and get a sense of what works and how well. Because of this, I have a very good idea of how many forces are necessary to take down different kinds of starbases, and what kinds of casualties / delay that will entail.
can i use the media hubs then i have 1 built thats close 2 phasejumps away can it overthrow it then i win.lol.
Yes, though you'll usually need 2-3 for every one the enemy has. Actually "turning" a planet with culture, particularly if they have a capital ship and culture stations of their own present, is very difficult. If you have them trapped on a single planet, though, this is a totally valid response.
the starbase is close to the gravity well as soon as you end your phasejump its right there in front of you
When making an offensive jump, follow this checklist:
1) Look before you leap: scout the target gravity well so you know what defenses are waiting there. Ensure you're ready to fight them or are capable of retreating. It's always a good idea to carry 8-12 scouts with your fleet just so you can sacrifice them for this purpose, plus then you have minesweepers. If you don't have scouts, flak frigates are your best alternative since they're inexpensive and more likely to survive than other unit types due to their incredible toughness.
2) Position Accordingly: If you line up your units, you have some control over where they will appear in the target gravity well. You can almost always avoid minefields and starbases in this manner. If you can't avoid the defenses entirely, be sure to move out of their range immediately after jumping in.
3) Ensure all your units are present and synced: You don't want your units to trickle in one at a time, so ensure your units are all synced with the right behaviors and are ready to jump simultaneously.
4) If you cannot avoid minefields, send a clearing force: 3 scouts and 5 flak frigates (give or take) is my typical clearing force. Warp them in and they'll almost instantly kill every mine in a radius around them. Within seconds they'll have punched a considerable hole in the minefield, giving the rest of your fleet and entry point.
i thought the kostura suppose to nail the planet not the structures
Kosturas only affect structures, damaging and disabling them. However, they also open a phase stabilizer gateway. This allows you to jump directly to the target world from anywhere that has a phase stabilizer. Once you have a kostura, you can literally invade any world you like. That's not significant in your current situation, unfortunately, so the kostura is more limited.
The TEC Novalith bombards planets (3500 per shot) and largely disables the economy of the planet afterwards. The Advent Deliverance Engine increases the fighting power of friendly units in the gravity well and creates friendly culture there (making it the only superweapon that can be used defensively).