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If I cast Silent Image on a boat, does it move with the boat or do I have to use an action to make it move with the boat?
The situation is this, my party is floating down a large river and I want to be able to use the Silent Image spell on the canoe to make it look like a large tree floating down the river to anyone from the tree line.
My assumption is that because I've placed the illusion on the floor of the canoe, it will just stick with the boat and I do not need to use an action to move it because the illusion is not moving but rather the canoe is moving and the illusion is just place on the canoe.
Of course, the illusion isn't perfect because part of the tree looks like someone started carving the bottom of a boat out of it, and well the tree has oddly positioned branches that obscure much of the part of the tree (where the ores might be seen while the party paddles.), but it's a tree non the less, especially to the passive observer.