Rukarumel on the battlefield with "Sliver" chosen.
Steps
Cast Crimson Kobolds by paying ({0} magic symbol) , and choosing to pay its replicate cost an arbitrarily large number of times by paying ({0} magic symbol) .
Crimson Kobolds triggers, creating a copy of it for each time its replicate cost was paid.
Resolve all Crimson Kobolds spells, causing the nontoken Crimson Kobolds to enter the battlefield, and creating a token copy of it for each time its replicate cost was paid.