This is the major issue with 'polytheistic' religions in RPGs... because there are so many gods it seems like each one only represents or gets ONE thing they and their followers find important. Thus Gruumsh defaults to "destruction!!!" and that's the first, last, and only thing that gets focused on for both the god and those that follow him.
Whereas [MENTION=6808925]Cyrinishad[/MENTION] made the absolutely correct point that...
Real-world religions have many different sects, divisions, interpretations, etc... It stands to reason that Fantasy religions would be the same, and that the PC should be encouraged to explore their own interpretation of their particular deity.
The Silver Flame in the Eberron Campaign Setting does this to a T, and I think it's because it's a "singular deity" religion. Which means with only one god everyone is willing to think and write about all the different groupings within it, all the different sects and beliefs that come out of it, and for a supposedly "good" religion there are plenty of self-serving, holier-than-thou, or even downright "evil" members within it.
Why do we never give that same breadth and thought to individual gods within a polytheistic religion? We
should. Every god has multiple things in their "spheres of influence", and each individual thing has many facets you can look at and use as which part of the god is important to you as a PC. Here's what the Forgotten Realms wiki lists as what is important to Gruumsh:
Gruumsh told his worshipers to do the following:
- Gather and breed, and your numbers shall flourish.
- Rise up in hordes and seize that which is rightfully yours.
- Raid. Kill. Conquer.
At face value, the easiest and most simplistic way to take it is "DESTROY EVERYTHING!". But what does that gain anyone within the religion? Sure, many worshippers will take these tenets at face value... but there would and should be others that take a more philosophical view of the tenets and try and suss out the underlying ideas of what Gruumsh might want.
If it was me, and I was going to play a halfork cleric of Gruumsh... while at the same time try and maintain party cohesion... I'd look at those three tenets and find a side aspect to his worship that could matter to me that wasn't JUST "kill, kill kill!!!"
And the the part that jumps out at me? It's Gruumsh's tenet of "Gather and breed, and your numbers shall flourish." So an important part of his ideals are maintaining the numbers of the orcish race. Orcs are hunted down and killed all the time by the other races, so procreation is exceedingly important so that they don't go extinct. That's quite possibly one of the reasons why halforks are probably the second most populous half-breed, because orcs will procreate with humans so that at least SOME part of the orcish line lives on (if a pure orc/orc birth is not possible). For your player's PC... perhaps it's BECAUSE of the fact that he's a halfork and grew up in the human world that he finds himself losing the orcish side of him. And Gruumsh is coming to him in order to help sustain orcish numbers. The PC isn't following Gruumsh because he wants to destroy everything... but in point of fact he wants to PROTECT the orcish race from extinction.
Looking at it through this prism, it can be exceedingly easy to not play the character as "evil". The PC could easily be "good"! Gruumsh has commanded some of his followers to keep the orcish race alive, so now the PC wants to reclaim his orc half, and do whatever it takes to make sure orcs as a race continue to thrive. Which
might also mean working directly with the other races to try and come to a "live and let live" accord so that the orcs are not all hunted down and killed on sight.
Now yes, there would still definitely be a faction within the church of Gruumsh who would see this "live and let live" ideal of some Gruumsh worshippers as a great smokescreen for the eventual re-rise of their race and eventual conquering of everybody else... but that faction might have no impact or connection to your PC. Your player's PC could just be an evangelist or missionary out in the so-called "civilized" world, trying to bridge the gap between their races so that orcs (and halforks) have a better chance to survive and flourish. And the other aspects of destruction might never actually come into play (especially if it would cause an obvious divide between the halfork and elf players.)
At least... this is my opinion on the matter.