First, I am not a no money spent player, but I was able to get Mantle 2 weeks ago spending “only” $200 (with no flipping, br runs, or WS awards). After starting out with terrible luck, Mookie was my only diamond after roughly 140 packs (digital deluxe, twitch drops, and 2 50 bundles), my luck turned.
In after game drops (all conquest on vet or AS): Bellinger, Harper, Marte, Diamond socks (when they were expensive), and the low end diamond mask.
In packs: 2 story, Matt Chapman, Lindor, Rendon, Hader, Alonso, and Altuve
All of those were from “free” packs (I didn’t buy any after the 100 on day 1) and all were pre-Mantle (I bought all the rest during the crash of the first diamond pack flash sale)
Since Mantle, I have pulled Morton, Ramirez, and Scherzer from affinity rewards.