There are two boxes. If you open a box, you get to keep the contents.
Omega is an omniscient oracle. Omega predicts what will happen if you open the first box and observe that it contains $100.
If Omega predicts that you will open the second box, then Omega puts $0 in both boxes.
If Omega predicts that you will not open the second box, then Omega puts $100 in both boxes.
You open the first box. It contains $100. Do you open the second box?
Answer
No. If you open the second box, that means you're being simulated by Omega. If you're being simulated by Omega, then opening the second box ends the simulation and kills you.
Extra Credit [Orthogonal Thinking]
You have not yet opened the first box. How do you generate (at least) $250 in profit? [Please use spoiler tags or equivalent obfuscation when discussing the extra credit.]
The root of this paradox is that the human notion of ‘self’ actually can refer to at least two things: the observer and the agent. FDT and similar updateless decision theories only really concern themselves with the second.
An FDT agent cannot really “die” as they do exist in all places of the universe at once. Whereas, as you have noticed, an observer can very much die in a finite thought experiment. In reality, there is no outside-text dictating what can happen and you would just get quantum-immortaled into hell instead.
This case is not really a scenario exposing a bug in FDT, it's rather FDT exposing an absurdity in the scenario's prior — stipulating that you should be only concerned with one copy of you (the one outside the simulation).
Thought experiments can arbitrarily decide that one copy of the agent does not correspond to an observer whose values should be catered to and therefore can be assigned a probability/utility of 0. But you, the one who implements the algorithm, cannot differentiate between yourselves based on whether they are simulated by Omega, only based on what you have observed.
There are two boxes. If you open a box, you get to keep the contents.
Omega is an omniscient oracle. Omega predicts what will happen if you open the first box and observe that it contains $100.
You open the first box. It contains $100. Do you open the second box?
Answer
No. If you open the second box, that means you're being simulated by Omega. If you're being simulated by Omega, then opening the second box ends the simulation and kills you.
Extra Credit [Orthogonal Thinking]
You have not yet opened the first box. How do you generate (at least) $250 in profit? [Please use spoiler tags or equivalent obfuscation when discussing the extra credit.]