For my team of Mia, Nowi, Brave Ike, Delthea what are the ideal ally support pairings and who should I summoner support as well?
I'd choose Delthea and Brave Ike , and Nowi and Mia. Brave Ike can cover Delthea with reposition after she attacks and then Brave ike will still be buffed by delthea. It's good for player phase and opponent phase. Nowi and Mia is pretty much the same analogy that after Mia attacks, Nowi can cover for her.
Same as fullrain, but for the summoner support, if you are going to run Mia around the map with Nowi as support, Id recommend supporting nowi so she can protect Mia after her attacks, if you want to bait with Brave Ike however I'd summoner support him to ensure that he can take the hits he has to. Then again the way you will use your team will dictate the summoner support, so Id see the unit that will be under the greatest pressure to perform and I'd summoner support that one.
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