To me, the question about giving PCs XP if the player does not show up has different aspects.
First there is the question about what XP are: a reward, as many posters have said, or rather a pacing mechanism.
XP lead to leveling up, so the PC gets better, hits harder, casts more spells, knows more maneuvers etc. And that can be a reward. But in itself, XP are not a reward, especially not an immediate reward. In 3rd edition, XP were a reward, because they were the currency with which a PC could construct magic items. I do not know of any such mechanism in 5e. Instead, XP now are a tool to measure how long it takes a PC to gain a reward. XP are a pacing mechanism.
Besides, there exist a number of real rewards that are immediate and work really well, namely gold and (magic) items.
If this is so, then why should a PC whose player cannot participate in the game not get XP? Is that PC not taking part in the pacing of the game itself? Especially because in most cases it would seem rather silly that the PC would just disappear. Now, if there is a plausible reason for the PC not to be there (for example in a game which consists of dungeon raids and every game session is about one of those raids) then this could be explained in-game. But green clouds (if that idea was meant to be a serious one to begin with) disturb my sense of believability immensly. YVMV.
However, if the PC is part of what is being played at the moment, he/she needs to take part in the pacing somehow. And since XP are a pacing device, the PC needs the XP, regardless of the fact that the player is not there.
The second thing about a missing player is whether the PC should be played as if that player were (was? grammar? Somebody tell me, please) there, with all options included (for example loss of limbs or life).
In my opinion this is a practical question that needs to be answered by the table. I know that it is possible to play two PCs with all the consequences at the same time. If the PC takes part in everything why not suffer the consequences? In our games, every PC is needed oftentimes in order to move further, so the option: "the Paladin just stands in the corner" simply does not exist.
This is something that should be handled according to what the table needs. And I am assuming that any player wants to show up and has a good reason not to (like when other, more important things in life than gaming get in the way).
If a player does not show up on a regular basis and cannot participate regularly anymore, it is something not related to the XP-issue. IMO there should be a discussion with that player and everybody else at the table about how to deal with this situation. In my current game, a player cannot participate for job reasons because he is in a different sity during the week. He does not play right now and we have found an in-game reason for his PC to not be around either. The DM has changed the combats and the pacing accordingly.
First there is the question about what XP are: a reward, as many posters have said, or rather a pacing mechanism.
XP lead to leveling up, so the PC gets better, hits harder, casts more spells, knows more maneuvers etc. And that can be a reward. But in itself, XP are not a reward, especially not an immediate reward. In 3rd edition, XP were a reward, because they were the currency with which a PC could construct magic items. I do not know of any such mechanism in 5e. Instead, XP now are a tool to measure how long it takes a PC to gain a reward. XP are a pacing mechanism.
Besides, there exist a number of real rewards that are immediate and work really well, namely gold and (magic) items.
If this is so, then why should a PC whose player cannot participate in the game not get XP? Is that PC not taking part in the pacing of the game itself? Especially because in most cases it would seem rather silly that the PC would just disappear. Now, if there is a plausible reason for the PC not to be there (for example in a game which consists of dungeon raids and every game session is about one of those raids) then this could be explained in-game. But green clouds (if that idea was meant to be a serious one to begin with) disturb my sense of believability immensly. YVMV.
However, if the PC is part of what is being played at the moment, he/she needs to take part in the pacing somehow. And since XP are a pacing device, the PC needs the XP, regardless of the fact that the player is not there.
The second thing about a missing player is whether the PC should be played as if that player were (was? grammar? Somebody tell me, please) there, with all options included (for example loss of limbs or life).
In my opinion this is a practical question that needs to be answered by the table. I know that it is possible to play two PCs with all the consequences at the same time. If the PC takes part in everything why not suffer the consequences? In our games, every PC is needed oftentimes in order to move further, so the option: "the Paladin just stands in the corner" simply does not exist.
This is something that should be handled according to what the table needs. And I am assuming that any player wants to show up and has a good reason not to (like when other, more important things in life than gaming get in the way).
If a player does not show up on a regular basis and cannot participate regularly anymore, it is something not related to the XP-issue. IMO there should be a discussion with that player and everybody else at the table about how to deal with this situation. In my current game, a player cannot participate for job reasons because he is in a different sity during the week. He does not play right now and we have found an in-game reason for his PC to not be around either. The DM has changed the combats and the pacing accordingly.