Farm raritanium?

[WatertownsFinest]

Is there any easy way? Do I even need to or will I have enough by the end of my challenge run?

[Yadilie]

You'll have a lot by the end of your Challenge Run just because of the card set bonuses. If you're really worried you can always upgrade the Sheepinator and use it on a majority of the enemies. It has a +% boost to Raritanium drops from enemies. Good news is that Omega weapons only add a couple more slots.

[baypoo]

If for some reason you don't have enough by the end of your Challenge Mode run, just play until you get to Aleero. When you have to "find a route to The Rangers", there's a helicopter, some dogs and 4 soldiers (shortly after purchasing station). You can use the Sheepinator to kill them all, then kill yourself after. The enemies don't respawn when you kill them and beat the level though. So make sure you kill yourself. This area works well for getting a lot of Raritanium, Holocards, and leveling up your weapons. 

[LetsTurnJu-On]

To be honest, I'm just gonna continue doing NG+ until I get it all done, probably will on my next playthrough (3rd time). Makes "the grind" seem like less of a grind if you're actually progressing, rather than just repeating the same small thing over and over.

Edited April 17, 2016 by LetsTurnJu-On

[SuperSaiyan3985]

I find it completely stupid to farm in a game like this, just play it for the fun for crying out loud. Anyways I got it by the end of my third playthrough on NG+ just beating enemies naturally. Although I did make sure to go back on my first playthrough and pick up all the raritanium on planets.

[baypoo]

In defense of farming in the sequence I mentioned, there's no fun Coliseum Mode this time. There are plenty of combat sequences, but frankly you will have to go through puzzle sequences, chase sequences, ship battles, and racing portions with more playthroughs. These parts were fun the first time or maybe even the second time. It's very possible you will be doing a third playthrough, though. It took 45 minutes to do that farming. 

 

Platinums are fun.  

[TheMotorDan]

Raritanium is easy to get in this game depending if you completed all the Holocard sets because most of the card sets allows for more Raritanium drops. Just keep killing yourself after a huge group of enemies and if you are lucky you can gain like 7-10 Raritanium each time. You can also find patches of three in different areas of a level. I did this in Challenge mode and ended up with 650 Raritanium. Here is the picture for proof along with the Platinum trophy:

 

Edited April 19, 2016 by TheMotorDan

[Robot500]

If you go to Rilgar there is an area with a gadgetron vendor above an area with a bunch of ameboid, DON'T JUMP DOWN THERE!!!! stay by the gadgetron vendor and keep shooting the ameboid and they will keep respawning and you can farm it quicker in challenge mode