Thrumming Stone | Memory Lapse | Bonus Round

Cards

({2} magic symbol) ({U} magic symbol) ({R} magic symbol) ({R} magic symbol) available.

Cast
Bonus Round by paying ({1} magic symbol) ({R} magic symbol) ({R} magic symbol) .
Thrumming Stone triggers, revealing the top four cards of your library and putting them on the bottom of your library.
Resolve
Bonus Round, copying all instants and sorceries cast after it this turn.
Cast any other spell, or wait for an opponent to cast one.
Cast
Memory Lapse by paying ({1} magic symbol) ({U} magic symbol) , targeting that spell.
Bonus Round and
Thrumming Stone trigger.
Resolve the
Bonus Round trigger, creating a copy of
Memory Lapse, targeting the original
Memory Lapse.
Resolve the copy of
Memory Lapse, countering the original
Memory Lapse and putting it on top of your library.
Resolve the
Thrumming Stone trigger from step 6, revealing the top four cards of your library and casting
Memory Lapse without paying its mana cost.
Repeat from step 6.