Then if there are three or more collection counters on it, sacrifice it
This is from an early press release
It's simple, effective, and shores up one of the weaknesses of the deck
Between Sliver Gravemother and Sliver Hivelord, both are acceptable commanders but I gotta give it to the Gravemother: encore is a powerful mechanic and even though the precon isn't really built around it outside of some discard or sacrifice slivers it's still a great way to get more value out of your deck, and the buildaround potential is huge
Burst Stream of Destruction is a flashy way to bring Raigeki back from the banned list, though it is situational, and therefore not always used
You have those cards at the top of the heap that demand the most value, and then even among the rare SIR prints, a bottom rung of cards that although still hits, are much less in demand