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From the more general "dying is useful/using your own corpse" idea, while it's a little broad, but there is nothing saying that Human Resources can't be drawn from one's own body. This is also a common trait of Liches in various series, becoming undead to obtain greater power.
The example you list of intentionally dying so your corpse accomplishes something might qualify as a Violation of Common Sense. "Being rewarded for doing something incredibly dangerous, idiotic..." Intentionally dying would seem to be at least that.
Not sure there is something specific for that. While interesting, it might be Too Rare to Trope.
Most generally, in the narrative sense, a character using their death to advance their goals may fall under My Death Is Just the Beginning (and see also Thanatos Gambit).
Expendable Clone and Cloning Gambit are at minimum closely related, especially if they take it to Me's a Crowd levels
I don't think it's that rare at all. Some other video game examples:
Hollow Knight - you can use your dead shade as a mobile boost jump point
Terraria - piling up your corpse gravestones is how you create the Graveyard biome
Spelunky 2 - in multiplayer, dying turns you into a helpful ghost with useful abilities. Your remaining corpse can also be used by your allies to activate triggers.
This trope is also related to, and the logical next step of: Death Is a Slap on the Wrist and Meaningless Lives
Edited by IronAnimationDeath as Game Mechanic when death is avoidable and Death Is the Only Option when it's not.
Edited by eroock

Is there a trope for when death is a useful option or directly brings a positive outcome?
I recall an online platformer game where dying is an essential mechanic, you have to die at certain places for your corpses to make a safe platform on spikes, to hold a button down, etc. Your last self's corpse remains where it died as you return to the Respawn Point every time.
I'm wondering if there could be non-video game examples, or instances that don't involve using your corpse as a tool. If there's a trope for that action in particular, I'd be happy to learn about it too.
Edited by BlackFaithStar