My account didn't level up

this! that's a good way to start on steamgifts. eventually there you will discover how level system works. :D

Everything listed here will give you 15 percent of it's real value.
https://www.steamgifts.com/bundle-games

Hello. Here's the list of all the currently bundled games: https://www.steamgifts.com/bundle-games
Usually, games that get a discount of 90% and above in any region, become bundled and that can affect your giveaway, even retroactively.

Anything not listed here, basically.
Bundled Games List

Though note that if something is in a bundle, such as over at HumbleBundle but isn't listed on the above page, that doesn't necessarily mean it won't get added retroactively at a later date. If bundled, or a 95% discount, assume it will be added from the date it appears.

Some games also get bundled at around 86% depending on the Russian prices, if they exceed the 95% threshold. Those are few and far between, but can affect even high profile games. The Talos Principle was one such example prior to showing up in later bundles anyway.