Passable for 2009 but outdated by modern standards; however, some jungle environments are decently lush.
There is a well-known free alternative called created by Xisumavoid. This is a Bed Wars-style map set entirely underground. Cost: Free to download for Minecraft Java Edition. Tunnel Rats Free Download
The commercial game, , is not free . It is currently available for purchase on Steam for approximately $20 . Passable for 2009 but outdated by modern standards;
If you do decide to play the 2009 version, it is highly lightweight by modern standards: Tunnel Rats Free Download