"Ominous" is a secret "easter egg" in Elements, which turns the module into a weird 2x2 operators FM synth voice. Think Braids' FM/FBFM times two. It lives in a strange middle-ground between classic subtractive analog and what you'd expect of FM.
How to activate it?
Set all the attenuverters and all the TIMBRE knobs of the Exciter section to their minimum position. Set all the attenuverters and the DAMPING, POSITION, and SPACE knobs of the Resonator section to their maximum position.
Hold the PLAY push-button for 5 seconds. Press PLAY again. The push-button's built-in LED should be off. You can now move the attenuverters and other knobs to their normal position.
How to get back to the normal modal synthesis firmware?
Same procedure as above.
How does it work?
The autopan / rotation is a quadrature LFO thingie that acts on both pan and a mild LPF - the result is an effect of source rotation / slow filter sweep / leslie / tremolo. The rotation rate for oscillator 1 and 2 is different, so there are interesting beating effects too.
CONTOUR: shape of the built-in envelope that is triggered by the PLAY button or the GATE input.
BOW: detuning of oscillator 2 with respect to oscillator 1. The range is -2 octaves to 2 octaves, with strategically placed notches.
BLOW: oscillator 1 level. May soft-clip past 12 o'clock.
STRIKE: oscillator 2 level. May soft-clip past 12 o'clock.
FLOW: oscillator 1 carrier/modulator frequency ratio. This control acts in similar fashion to the COLOR knob of Braids' FM models: it has virtual notches at interesting frequency ratios, such as those found on Yamaha's DX series synths. 12 o'clock gives a 1:1 frequency ratio.
MALLET: oscillator 2 carrier/modulator frequency ratio. Same scale as above.
(BOW) TIMBRE: oscillator 1 & 2 feedback amount. This increases the amount of phase feedback of both oscillators - progressively making them harsher and more chaotic (like morphing from Braids' FM to FBFM).
(BLOW) TIMBRE: oscillator 1 FM amount.
(STRIKE) TIMBRE: oscillator 2 FM amount.
Wow! You can also use the BLOW/STRIKE external inputs for audio-rate phase modulation of both oscillators.
COARSE/FINE/FM: coarse/fine frequency, and exponential FM of both oscillators 1 and 2.
GEOMETRY: response of the stereo filter. This interpolates between low-pass, notch, high-pass, and finally band-pass. The filter has a mild resonance. No dedicated resonance control because it's kind of silly on FM timbres.
BRIGHTNESS: cutoff frequency of the stereo filter.
DAMPING: amount of filter modulation from the internal envelope and the STRENGTH CV input.
POSITION: speed of the stereo rotation.
SPACE: mixing configuration. When set to its minimum value, OUT L contains the raw mix of both oscillators, and OUT R a mono signal without spatialization (but with the filter and VCA). When turning the knob further, you reach a zone where the stereo rotation becomes more intense. Past 12 o'clock, the reverb kicks in.
https://soundcloud.com/mutable-instruments/ominous
cool-COOL!! Can't wait to try this out (once my Elements and Clouds modules, which are finally on their way to me, have arrived 
)!! 
Now everyone needs a second Elements to pass through Elements.
