So... here's my take:
1) If you want your character to continue, just depower him in some way. The aforementioned loss of magic items and the lowering of stats from an injury would both be pretty effective. Also an option would be a Curse that can later be lifted when the rest of the party has caught up in power level.
2) Spectacular Death (Death that is itself a Spectacle) can also be really big and powerful. 100%.
3) NPCdom. Your character may be needed to fulfill some specific aspect of the quest that requires them to depart the party, and then your new character is introduced from NPC Status to help the party in his absence (And possibly betray them if your new character is secretly part of an evil plot)
Each has it's own narrative power. Talk with your DM about which solution would be most effective.
1) If you want your character to continue, just depower him in some way. The aforementioned loss of magic items and the lowering of stats from an injury would both be pretty effective. Also an option would be a Curse that can later be lifted when the rest of the party has caught up in power level.
2) Spectacular Death (Death that is itself a Spectacle) can also be really big and powerful. 100%.
3) NPCdom. Your character may be needed to fulfill some specific aspect of the quest that requires them to depart the party, and then your new character is introduced from NPC Status to help the party in his absence (And possibly betray them if your new character is secretly part of an evil plot)
Each has it's own narrative power. Talk with your DM about which solution would be most effective.