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Wall of Fire description:
You create a wall of fire on a solid surface within range. You can make the wall up to 60 feet long, 20 feet high, and 1 foot thick, or a ringed wall up to 20 feet in diameter, 20 feet high, and 1 foot thick. The wall is opaque and lasts for the duration. When the wall appears, each creature within its area must make a Dexterity saving throw. On a failed save, a creature takes 5d8 fire damage, or half as much damage on a successful save. One side of the wall, selected by you when you cast this spell, deals 5d8 fire damage to each creature that ends its turn within 10 feet of that side or inside the wall. A creature takes the same damage when it enters the wall for the first time on a turn or ends its turn there. The other side of the wall deals no damage.
Now consider the following scenario: a wizard casts Wall of Fire against two targets T1 and T2, as the figure below shows. The side of the wall that deals damage is the inner one. Suppose that the initiative order is Wizard->T1->T2. Is the following interpretation correct?
1 - The wizard casts WoF. T1 makes a saving throw and takes damage accordingly.
2 - T1 runs away. No further damage for him.
3a - T2 does not move. At the end of its turn, he takes 5d8 fire damage
3b - T2 crosses the wall and runs away. He takes 5d8 fire damage