Syser claimed to be that replacement. But in fact it's too old, unstable and nobody using it. Now everyone is using WinDbg for kernel/drivers debugging. It has terrible command syntax, but with PyKD extension and some customisation it's usable. See those slides[1] on how to do that. Also, there is another way to work with WinDbg protocol - using radare2[2]. Beware this support is in early development and may be unstable. But, unlike original WinDbg, it is cross-platform tool without external dependencies and completely free and open source.
[1] https://www.botconf.eu/wp-content/uploads/2014/12/2014-2.1-W...
[2] https://github.com/radare/radare2/blob/master/doc/windbg