In a recent article, I mentioned how the particle を (wo or o) is usually not used in combination with other particles, except for “をも” (wo mo) which you can occasionally see in literature. However I came across another combination involving を I wanted to talk about, just to set the record straight: をば (wo ba).
「をば」 actually comes from a combination of two particles, を (wo) and は (wa). However, in this combination the latter is vocalized (in a process called 濁音化) and becomes ば (ba). While the は particle has several uses (and together with が is arguably one of the more difficult for English-speakers to properly learn), in をば it is being used simply for emphasis (強調).
This pair of particles is used mostly in classic Japanese. For example, you can find it in the famous work Man’yōshū which is the oldest collection of Japanese poetry, written roughly in the time period 600-800 AD. I have read that it can still be used in modern times when an author wants to give an extra formal or old-fashioned feel to some text. I have very rarely seen this particle duo myself, but did come across it recently when reading some Japanese that was over 50 years old.
For the above reasons, you are unlikely to need to use this in any if your writing or speaking.
By the way, when I first saw をば I thought it was a dialect I had seen in a book or manga somewhere. It turns out that even in modern times, in Kyuushuu dialect (九州弁) the direct object can be specified with ば instead of を. Apparently this is an abbreviation of をば. I think it’s interesting to follow the history of expressions like this.