After the first time you foretell this, I promise you that your opponent will be panicking that every single foretold card is a copy of Starnheim Unleashed
Here's my Commander: She costs five, has flash and convoke, double strike, and gives your tapped stuff hexproof to protect them from removal or interaction
Once a creature has attacked, this can be any time the turn it declared an attack, they can pay the Boast cost once to activate its effect
You can also add a bit of jank that you can safely discard to play lands from outside the game, making this a pretty great card
My theory is that any deck led by my Genju of the Realms is going to be incredibly angry at us all
Eldrazi midrange gained new teeth with Emrakul, the World Anew , while energy counters and free Flare spells gave players fresh engines and interaction