Cloud Key
Artifact
As this artifact enters, choose artifact, creature, enchantment, instant, or sorcery.
Spells you cast of the chosen type cost 
less to cast.
Why is this card good?
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Related cards
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Printings (7)
Played by these commanders
Combos (8)
- Sensei's Divining Top + Cloud Key + Mystic Forge
→ Infinite card draw, Near-infinite storm count, Infinite draw triggers
- Sensei's Divining Top + Cloud Key + The Reality Chip
→ Infinite card draw, Infinite draw triggers, Near-infinite storm count
- Scrap Trawler + Myr Retriever + Krark-Clan Ironworks + Cloud Key
→ Infinite ETB, Infinite LTB, Infinite colorless mana
- Sensei's Divining Top + Cloud Key + Crystal Skull, Isu Spyglass
→ Infinite card draw, Near-infinite storm count, Infinite draw triggers
- Scrap Trawler + Myr Retriever + Ashnod's Altar + Cloud Key
→ Infinite ETB, Infinite LTB, Infinite colorless mana
- Urza, Lord High Artificer + Forensic Gadgeteer + Sensei's Divining Top + Cloud Key
→ Infinite card draw, Infinite draw triggers, Near-infinite storm count
Rulings (2)
- 2021-03-19
The cost reduction applies only to generic mana in the cost of spells of the chosen type you cast.
- 2021-03-19
To determine the total cost of a spell, start with the mana cost or alternative cost you're paying (such as a flashback cost), add any cost increases (such as kicker costs), then apply any cost reductions (such as that of Cloud Key's ability). The mana value of the spell is determined by only its mana cost, no matter what the total cost to cast that spell was.