Reflection Robbery (Casual)

Basic Idea:

Fill up the enemy board with things that, under normal circumstances, nobody wants to have on their board. In this case we talk about Sleeper Agent and Goblin Construct Tokens generated by Relic Robber.

With the print of Mystic Reflection, we now have a fun tool to multiply those annoying things, and spam the enemy board with pesky self-pingers.

Some fun interactions:

Turn 2: Foretell Mystic Reflection
Turn 3: Relic Robber and swing for one Goblin Construct
Turn 4: Hunted Phantasm and in response to the ETB trigger the foretold Mystic Reflection targeting the Goblin Construct.
-->6 Damage Every Upkeep if not dealt with, Sleeper Agent would also be a valid target for Mystic Reflection, but make sure the upkeep ping kills the opponent. Otherwise you are in for a hurtful swing if you don't have mana open for echoing truth.

Turn 2: Foretell Mystic Reflection
Turn 3: Dragon Fodder, and in response the foretold Mystic Reflection targeting their creature
-->2 copies of their strongest creature

You can also copy your Relic Robber or Rampaging Ferocidon.

Bonus: Any 1 or more Rampaging Ferocidon makes Hunted Phantasm an potentially lethal to-the-face-cannon.

If you have a Rampaging Ferocidon and play a Sleeper Agent, make sure to order the triggers on the stack, so that Sleeper Agents ETB Trigger resolves first, making Rampaging Ferocidon pinging the opponent for 1 extra damage instead of you, because as the trigger resolves, your opponent already controls the Sleeper Agent.

Turn 5: Foretell Mystic Reflection
Turn 6: Hunted Phantasm, in response to the ETB trigger the foretold Mystic Reflection targeting the Hunted Phantasm, giving your opponent 5 of these. Therefore you get 25 Goblin tokens. Afterwards Echoing Truth targeting Hunted Phantasm and pray it doesn't get countered.