If you're looking for the ability to play chords / polyphonic synths in a small Eurorack module, this is a great place to start. The ability to store chord voicings is great as well as the ability to play via MIDI.

Description from ModularGrid

Poly Cinematic. The powerful compact synthesiser that brings big synth polyphony to Eurorack. Simple to use with immediate control over your sound without any hidden menus. Poly Cinematic can be played both with a midi keyboard and without, since it can memorise the last 8 chord shapes you played it opens up fantastic opportunities as a CV/Gate module to create massive stacked sounds and sequenced chord progressions.
Here is a list of main features:
8 fully polyphonic voices each including...
• 7 oscillator super saw
• 3 oscillator syncable square/pulse
• 3 oscillator tone wheel generator
• chord memory triggered by cv/gate
• built in high definition stereo reverb
• 3 filter types