The Hunter's Mark spell states:
You choose a creature you can see within range and mystically mark it as your quarry. Until the spell ends, you deal an extra 1d6 damage to the target whenever you hit it with a weapon attack, and you have advantage on any Wisdom (Perception) or Wisdom (Survival) check you make to find it. If the target drops to 0 hit points before this spell ends, you can use a bonus action on a subsequent turn of yours to mark a new creature.
Here are the rules on combining magical effects:
The effects of different spells add together while the durations of those spells overlap. The effects of the same spell cast multiple times don't combine, however. Instead, the most potent effect--such as the highest bonus--from those castings applies while their durations overlap, or the most recent effect applies if the castings are equally potent and their durations overlap.
For example, if two clerics cast bless on the same target, that character gains the spell's benefit only once; he or she doesn't get to roll two bonus dice.
An interesting situation came up in tonight's game where both a comrade (vengeance paladin) and myself (ranger) cast Hunter's Mark on the same target and attacked it on our respective turns. I am wondering whether the above rule on combining magical effects should have prevented both of us from benefiting from casting Hunter's Mark on that same target or not.
The reason I'm unsure is that unlike Bless, which solely affects the target(s), Hunter's Mark seems to be more of a link between the caster and the target, and in some way, the caster is also the target of the spell... I don't know how to phrase it well.
Can more than one creature benefit from multiple Hunter's Mark spells cast on the same target?