Try playing as Vasari Loyalists. They can become completely fleet-based, and destroy planets outright for huge resource boosts. It's easy to play when you have nothing to defend and leave nothing behind for your enemies to colonize. In the game I just played, the TEC defeated every other player just with its novaliths, but because I had a single huge fleet and no territory to worry about, I swept them aside.

I love the Advent, but there's nothing you can do about hostile novaliths except destroy them. Maybe try allying with the TEC players next game.

Well if you dont want to build the SB's the only thing you can do is go after the Novalith's themselves. As far as how the AI knows to kill the planet once you recolonize, it doesn't. It has the autocast on for the cannon which auto targets any of your owned planets. It seems to generally prefer to shoot at previous targets, if possible. The AI also probably has more than one cannon. If you absolutely dont want to build the SB's then Advent have a tech in the Defence tree that reduces bombing damage to planets (probably wont help too much though).

Bottom line, just build the SB's. With 10 planets you should have a decent enough economy to be able to build them and put the Enduring Devotion upgrade on them. Sounds like maybe your economy isn't where it could be.

Well my strategy as either vasari race is that when a hear that a novalith cannon is being built ill simply fire a kostura shell at the planet then phase my fleet in then destroy the cannon and as much other stuff as i can then use my marauder stabilize phase space to phase out

Shield generators + emergency facilities will protect you from a novalith if ur TEC, auxillary govt works aswell.

for advent obviously enduring devotion.

Novaliths if anything imo they are slightly underpowered especially in big games where ur limited to 4.

Perhaps this is all they were intended for but they are a weapon of attrition, not instant devastation.

All they do against better players is reduce income significantly from constant bombardment of ur population so, they are merely a very expensive method of economic warfare against an enemy. So unless ur TEC loyals who simply need that economic advantage to slowly grind you down to win late game as their titan and fleet on the OFFENSE cant really stand toe to toe with the other races in an unfriendly gravity well, They arent worth getting if ur TEC rebels.

Well thats my assesment anyway. Against less experienced players yes they win games, but once ur up against a player that can mostly shrug them off.... "meh, well that was an expensive waste"

Kostura cannon on the other hand... thats the equivalent of a Tsar bomba being dropped on ur home planet when its used to insta phase jump vas fleet from anywhere plus disables all structures for a LONG time. Absolute pain in the ass if its spammed on ur fleet production planets too.