Pinnacle Starcage will be vital to the Azorius Control archetype for the same reason Temporary Lockdown was - it helps stop early aggression
Normally, on a legendary creature, this is very bad, but The Master planned ahead with this and comes with a fun anti-legend rule clause, letting you have as many token copies of it as you like
When Disneys cultural production juggernaut parks in your front yard, you dont make a fuss about the ruined grass
However, this Spell Card lets you use monsters from your Deck as Fusion Material (in addition to your hand and field), so if you put "Red-Eyes B
Besides, you have to block menace creatures with multiple blockers anyway, so you might as well assign those blockers properly to prevent another round of attacks from the menace creature