Aethergeode Miner does not have summoning sickness.
An opponent is unable to block and kill Aethergeode Miner and Lightning Runner.
Steps
Declare Aethergeode Miner and Lightning Runner as attackers, triggering their abilities twice each.
Resolve both Aethergeode Miner triggers, causing you to get ({E} magic symbol) ({E} magic symbol) ({E} magic symbol) ({E} magic symbol) .
Resolve the first Lightning Runner trigger, causing you to get ({E} magic symbol) ({E} magic symbol) and choosing not to pay.
Resolve the second Lightning Runner trigger, causing you to get ({E} magic symbol) ({E} magic symbol) and pay eight ({E} magic symbol) to untap all creatures you control and to get an additional combat phase after this one.