In 4e D&D, there are three possibilities:
The first is, by default, a DC 10 Healing check standard action, requiring adjacency. As a prayer, I would probably adjudicate it as a Medium DC Religion check, and perhaps be a bit more relaxed about the range.
The second is emulating a typical leader minor action encounter power. As a standard action prayer, I think it would be similar to the above, but with a fail causing d8+ level psychic damage (from the anguish of the prayer being ignored).
The third is emulating a cleric standard action daily power, or (with healing surge sacrifice) a paladin minor action daily power. That would require the player of the fighter to sacrifice something - probably two healing surges plus some magic item or ability that is appropriate in the fiction.
*The player of the fighter is trying to trigger their ally's second wind, and second wind hasn't been used yet since the last short rest;
*The player of the fighter is trying to trigger their ally's second wind, and second wind hasn't been used yet since the last short rest;
*The player of the fighter is trying to grant surgeless healing.
*The player of the fighter is trying to trigger their ally's second wind, and second wind hasn't been used yet since the last short rest;
*The player of the fighter is trying to grant surgeless healing.
The first is, by default, a DC 10 Healing check standard action, requiring adjacency. As a prayer, I would probably adjudicate it as a Medium DC Religion check, and perhaps be a bit more relaxed about the range.
The second is emulating a typical leader minor action encounter power. As a standard action prayer, I think it would be similar to the above, but with a fail causing d8+ level psychic damage (from the anguish of the prayer being ignored).
The third is emulating a cleric standard action daily power, or (with healing surge sacrifice) a paladin minor action daily power. That would require the player of the fighter to sacrifice something - probably two healing surges plus some magic item or ability that is appropriate in the fiction.