Keen Engineering is a mono-blue artifact Commander deck led by Sai, Master Thopterist. Casting artifacts steadily builds a fleet of evasive Thopter tokens, while Sai can turn spare artifacts into fresh cards. Cost reducers, mana rocks, affinity spells, and artifact-based card draw help the deck establish a dense battlefield quickly without running out of resources. Its primary pressure comes from going wide with flying artifact creatures, then enhancing that board through Master of Etherium, Chief of the Foundry, Steel Overseer, Forsaken Monument, or Graaz, Unstoppable Juggernaut. Larger artifact threats such as Kappa Cannoneer, Myr Battlesphere, and Steel Hellkite provide decisive attacks, while Psychosis Crawler offers a secondary drain-based finish. Counterspells, bounce effects, Propaganda, and selective removal give the list a measured interactive pace, and recursion from Myr Retriever and Buried Ruin adds resilience after trades or sweepers. Players who enjoy incremental value, artifact synergies, and flexible blue play patterns will find ample room for upgrades in token payoffs, artifact recursion, and stronger mana acceleration.