@AliceWinsor,

Here is one way I think it could be done:
1. In a block prior to your randomizer, create a MC question with a choice for each of your 30 target items. Use Advanced Randomization to evenly select 15. Hide the question with JavaScript (`jQuery("#"+this.questionId).hide();`).
2. Create another question just like the above for each of your 30 lure items.
3. Put all your target and lure blocks under one randomizer and present all 60 items
4. Create a branch for each target/lure block (put the target/lure block under the branch). The branch condition should be if the target/lure was displayed in the applicable hidden question you created in step 1 and 2 above.

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