Cast Realm-Scorcher Hellkite by paying 4 and sacrificing another artifact, enchantment or token.
When Realm-Scorcher Hellkite enters the battlefield, it and Miirym trigger twice.
Resolve both Realm-Scorcher Hellkite triggers, adding 5.
Resolve both Miirym triggers, creating two token copies of Realm-Scorcher Hellkite.
Activate Temur Sabertooth by paying 1, returning Realm-Scorcher Hellkite to your hand from the battlefield.
Repeat.
This explosive loop transforms a single Dragon into a self-sustaining engine of mana and clones. As soon as you cast Realm-Scorcher Hellkite with its bargain cost paid, Virtue of Knowledge doubles its entry triggers to yield a massive influx of mana. At the same time, Miirym, Sentinel Wyrm uses that same double-trigger benefit to flood the board with non-legendary token copies of the Hellkite. You then use Temur Sabertooth's activated ability to bounce the original Realm-Scorcher Hellkite back to your hand, leaving you with enough leftover mana and tokens to recast it and repeat the entire spectacle indefinitely.