Research Construction, then Troops. Design some Troops and build them. Design a troop transport ship (give it the type of Troop Transport), and build it. Load up troops. Send it with a fleet to attack a planet. Move it next to the planet (in combat), and use the Drop Troops order.
Originally posted by Imperator Fyron: Space Monsters are supposed to be extremely tough. Research Mines (need Construction tech first) and deploy minefields over planets and critical WPs. This will help against monster raids (as well as other AIs).
what are you kidding? are your monsters different from Rollo's Devnull Monsters? if they are the same, deploying mines over planets will bring out the monster 'mine-sweepers' that destroy population and planetary conditions, leaving barren and dead worlds.
but yes, the monsters are there for advanced players who want a better challenge. we all (well, most of us) had the same struggles at the beginning, but after a few months you will be looking for more ways to make the game harder.
fortuneatly, there are several years of community modding effort out there that will help to beef up the game. some of which you have already found
__________________
...the green, sticky spawn of the stars
(with apologies to H.P.L.)