Absolutely worth it.

Good Spider progression champ, has uses in Doom Tower, Hydra and Faction Wars (though has issues in late game against Valkyrie waves, but that's an issue for down the road)

The short answer is "yes". The long answer is - it depends a lot on who else you have. For example, personally I never used Drex because I got Ignatius as one of my first lego champs, and then later got Tyrant.

Doesn't need books, can be useful in spider and Hard DT at 5stars.... buy the fragments every day... absolute no Brainer.

AND DONT SAVE!  U CAN ONLY BUY 1 EVERY 24 HOURS 

I may have done this for the first few weeks :D

Even if you dont need him , worth getting the fragments anyway , its always good to have a leggo to pull during a champ chase for a fusion . 

I saved up enough to buy all 100.

I was sick as a dog when I bought that first shard.

I didnt have any kind of decent HP burn champ at all at the time.