Blood Moon vs. the Dryad
Corner CasesNo dependency this time: the Dryad turns Mountains into rainbow lands — if she came later.
Cards involved
The setup
Your opponent controls Blood Moon. AFTERWARDS you play Dryad of the Ilysian Grove: "Lands you control are every basic land type in addition to their other types."
What happens?
What are your nonbasic lands now?
The L3 classic since 2020:
Pick an answer to continue.
The difference from Urborg: the Dryad is a CREATURE, not a land — Blood Moon can't strip her ability. Neither effect changes what the other does or applies to ("basic" is a supertype and stays untouched) → no dependency (613.8) → timestamp order (613.7). Dryad later: Mountains + all basic types. Blood Moon later: just Mountains.
613.7Within a layer or sublayer, determining which order effects are applied in is usually done using a timestamp system. An effect with an earlier timestamp is applied before an effect with a later timestamp.
613.8Within a layer or sublayer, determining which order effects are applied in is sometimes done using a dependency system. If a dependency exists, it will override the timestamp system.
The detailed analysis
Both work in layer 4. Blood Moon SETS the type (Mountain, other land types and abilities gone), the Dryad ADDS types. Applied in timestamp order, that produces two completely different mana bases — and your lands remain nonbasic throughout.
613.8Within a layer or sublayer, determining which order effects are applied in is sometimes done using a dependency system. If a dependency exists, it will override the timestamp system.
613.7Within a layer or sublayer, determining which order effects are applied in is usually done using a timestamp system. An effect with an earlier timestamp is applied before an effect with a later timestamp.
The L3 rule of thumb
ALWAYS ask the dependency question first: "Does A change what B does, what it applies to, or whether it exists?" Only if both answers are no does the clock decide. Urborg: dependency (Blood Moon strips the ability). Dryad: timestamp.
613.8Within a layer or sublayer, determining which order effects are applied in is sometimes done using a dependency system. If a dependency exists, it will override the timestamp system.
Stack
Blood Moon
Nonbasic lands are Mountains
Dryad of the Ilysian Grove
Your lands are every basic land type in addition
The stack is empty.
Battlefield
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