Hey guys, been playing a while and this came up today. Might have been playing it wrong for years!
If someone says they want to change phases, and responses occur, after that is resolved will it be in the original phase or the new one?
For example, I move to the combat phase. "In response" my opponent attempts to path my creature. I counter that spell. Are we now in the combat phase, or in the main phase and I have to attempt to change phases again?
In general, a step or phase where players get priority, including the main phase, ends only if all players pass in a row while the stack is empty (C.R. 500.2, 505.5). Just because all spells and abilities on the stack have resolved, that alone doesn't end a step or phase (C.R. 500.2).
Also, by saying you will move to combat, you are merely proposing a shortcut that any other player can shorten (C.R. 721.2a-b; for sanctioned tournaments, see M.T.R. 4.2). For example, after you say "move to combat" during your first main phase, your opponent can shorten this shortcut by proposing to cast an instant spell (such as Path to Exile) during that same main phase; if they do, and no one else shortens or has shortened the shortcut further, the opponent will get to cast that spell and the game will still be in your first main phase (C.R. 721.2a-c, 115.1a; for sanctioned tournaments, see M.T.R. 4.2).
FYI
Your title contains the words 'instant speed'; this could indicate an erroneous understanding of how instants differ from sorceries.
The real difference between instants and sorceries is not HOW FAST they get played but rather WHEN they're allowed be played.
Instants spells (and abilities) don't go any faster than sorceries or creature spells: all resolve at the same rate. Instants' sole advantage is that you're allowed to play them almost anytime, while sorceries can be played only during either of your Main Phases (among other criteria).
If someone says they want to change phases, and responses occur, after that is resolved will it be in the original phase or the new one?
For example, I move to the combat phase. "In response" my opponent attempts to path my creature. I counter that spell. Are we now in the combat phase, or in the main phase and I have to attempt to change phases again?
Thanks a lot for the assist!
Also, by saying you will move to combat, you are merely proposing a shortcut that any other player can shorten (C.R. 721.2a-b; for sanctioned tournaments, see M.T.R. 4.2). For example, after you say "move to combat" during your first main phase, your opponent can shorten this shortcut by proposing to cast an instant spell (such as Path to Exile) during that same main phase; if they do, and no one else shortens or has shortened the shortcut further, the opponent will get to cast that spell and the game will still be in your first main phase (C.R. 721.2a-c, 115.1a; for sanctioned tournaments, see M.T.R. 4.2).
See also this thread.
Your title contains the words 'instant speed'; this could indicate an erroneous understanding of how instants differ from sorceries.
The real difference between instants and sorceries is not HOW FAST they get played but rather WHEN they're allowed be played.
Instants spells (and abilities) don't go any faster than sorceries or creature spells: all resolve at the same rate. Instants' sole advantage is that you're allowed to play them almost anytime, while sorceries can be played only during either of your Main Phases (among other criteria).
Take a look at rule 117.1a for details:
https://magic.wizards.com/en/game-info/gameplay/rules-and-formats/rules
RULES OF MAGIC :
http://magic.wizards.com/en/game-info/gameplay/rules-and-formats/rules