Is there an easy way to get ether crystals for Poppi?

So I've just unlocked the last form for Poppi and while it should make Tora more useful again, to really power him up will require a load of ether crystals.

Is playing Tiger! Tiger! the only way to get them? If so what is the best way to get them quickly?

It seems that playing the first level repeatedly is the way to go as it's easier but I'm not sure if you get more crystals in the later levels or something...

Solution 1:

Yes, playing Tiger! Tiger! is the only way to get ether crystals. You should repeatedly play the last stage (in easy mode, if you prefer) and at the very least get each treasure. This is the only stage that can drop master mods, as well as dropping other high level items.

You can convert any unwanted items earned from Tiger! Tiger! (skills, mods, etc) into ether, which will contribute pretty significantly to your ether totals.

Lastly, you can get 30,000 ether crystals by buying the DLC Expansion Pass, but it's not repeatable, so you'll likely burn through it fairly quickly.

Solution 2:

As of Patch 1.3.0, in New Game Plus, you can find a travelling bard in Torigoth, Gormott, who will sell you 20,000 Ether Crystals for 200,000 Bonus Experience as many times as you like.

Solution 3:

Another way to farm ether crystals is to grind for Noponstones in the land of challenge from the dlc. T he noponstones can then be used to buy parts for popp i from one of the land of challenge nopons. Those parts are only 5 nopon stones but can be crystallized for 1128 ether crystals each. So 995 nopon stones become 224472 ether crystals. It's not fast but grinding up my w p i was collecting thousands of nopon stones and didn't immediately figure out the plan to use them to power up poppi.