How: The Planet could either come close to each other and the gravitational pull collides them together and destroys them and after a few days ( in game ) a new planet forms with better or worse ores that were on there from extreme heat and pressure. Do it your self: You could put huge industrial thrusters on one side of the planet until it smashed another or you could make a gravitational magnet to bring in another planet. How it looks in the background: The incoming planet would be small at first but everyday that passes it becomes bigger and when it is about to hit the surface temperature heats up and when it hits the ground will become "unstable" to stand on for a few days there for making big changes to planets. Anymore Ideas!? Preventing this on your home world: Make a Gravitational Magnet that repels any meteors and or planet sized objects that could threaten your world. Effects on Planet: The planets Ores become more Enhanced. The Planets Ores become less Enhanced. The Enhancement includes better defense, better resistance to lava, acid, and etc. Any ideas!?! ^^ This could also be negative effects on Ores ^^ Any More Ideas put them in the comments and ill add them to the Thread
Extreme temperatures and pressures would create better ores in your idea , because they make possible the creation of more dense , and rare , metals. But that shouldn't happen , because only supernovas create such things , you'll need 15 billion celsius degrees with a collision ( considering the pressure is enough ).
Then maybe somebody should make it so stars or galaxies can collide? Super Novas could happen then maybe? Or maybe just have stars grow older?
Supernovas happen when a star that is at least 10 times bigger than our Sun die , and that may take billions of years to happen.Thats the only way a supernova happens.
I don't think planets should be able to collide in game, I think you should just find them that way. Oh and by the way, this seems very similar to my idea I posted a few days ago: http://community.playstarbound.com/index.php?threads/crashed-planets.7943/