It got pushed back, we ended up looking at our priorities and this wasn't a huge one. We got a lot of good feedback on it (and a lot of users really liked it) and we wanted to make it so that minions and other items came from this method (you had a chance of "catching" them, like pokémon) but we just didn't have the pool going forward to do that and the other things we wanted to do. It was also a huge time sink for us (applying types / abilities to each minion, testing them in battle, etc) that we couldn't really keep up with while working on other projects.

It's something that is 90% done so we're going to revisit it :)

[edit]

As far as time goes - bonding was pretty easy to code. It was a cool way to get minions out, and we're really happy with how it's turned out. Minion battling required way more time, and from way more people. We were spending a lot of time coming up with the moves, figuring out the math, choosing which minions would be better than others, going through all of the r101+ minions on the site and sorting them into categories based on how frequent they are on the site, things like that. It was a huge undertaking that we didn't really anticipate at the start.

you won't lose them. it's not going to be scrapped completely.

but even in the highly unlikely chance that it is, there will definitely be an option to remove any minions you stored in the zoo that won't ever go away as long as there are still minions there. :)