A system, where a user can gift subs to the community, which the community can claim, and creators and mods can create a sub pool to collect subs, that can be claimed.

The creators can activate these under "Creator Dashboard > Affiliate / Partner > Subscriptions > Receive claimable Subscriptions"

The user, who gifts subscriptions to the community, can click on "Claimable Subscription". A panel opens up, that looks like this: https://panels.twitch.tv/panel-484294793-image-b03745c6-8228-4d17-9016-7213abf1a58b (sorry for the poor quality, but the compression really hit).
In there, the user can title the claimable sub, like asking a question. To the question, the user has to provide answer(s) which the viewers have to answer in order to receive the sub.
The user also specified a time limit. After the time has run out and nobody has given the correct answer, or some subs are still available to be received, the sub(s) will be gifted to the community as usual.
After the user has send out the claimable sub, a small information appears at the top of the chat. The information contains the title, the timer, and a text field for the viewer to write the answer.
The fastest correct answers receive one of the available subscriptions.
If someone gave a wrong answer, they cannot answer another time. Unless the option "Multiple submissions" is active.

This can also be combined with the prediction system, where the creators and the mods are able to give the correct answer.
The creators or the mods can open up a pool to collect subs. For example: "How many games until I win?" is the title of the pool. An Information appears at the top of the chat, with the title, the number of subs in the pool, and the timer. Everyone can contribute subs for the pool at any time. The creator or the mods can either choose a "text field answer" for the viewers to give a custom answer, or (like in the prediction system) possible answers.

If there are more people that guessed correctly than available subs, either the fastest answers will receive a subscription, or random correct answers will receive a subscription. That is up to the creators or mods.
If there are less people that guessed correctly than available subs, the rest of the subs are gifted to the community as usual.