Shiny Shadow Mewtwo confirmed : r/TheSilphRoad

Shadow Mewtwo battle confirmed (not as a reward though) : r/TheSilphRoad

Shadow Legendary Raids Spawning in New Zealand : r/TheSilphRoad

Cracking Voltage & Team GO Rocket Takeover : r/TheSilphRoad

A. Mewtwo Infographic Updated : r/TheSilphRoad

Shadow raids early release : r/TheSilphRoad

Original announcement implied Shadow Zapdos would be around for the season Adventures Abound, and not just September. : r/TheSilphRoad

Shiny Shadow Mewtwo Debuts in Shadow Raids

Distance glitch for buddy walk distance on Shadow Mewtwo? : r/TheSilphRoad

Shiny Shadow Mewtwo is HERE to Debut *Shadow Raids*

Not sure if this needed confirmation, but shadow legendaries can be Tiny or Huge, just caught a tiny shadow registeel : r/TheSilphRoad

Confirmed by a friend in Kiribati, Arlo has Nidoran Male as his Pokemon, Research page 1 and his potential team. : r/TheSilphRoad

Pokémon GO Hub on X: SHINY SHADOW MEWTWO RAIDS. That's the tweet. Just kidding, learn everything about the upcoming Rising Shadows event that introduces Shadow Raids in Pokémon GO on May 22