I know i'm late, but here are my 2cents
There are IMO 3 ways to play Harlequins atm, we can argue what is better but all are very close to being about the same.
1) Fusion spam
2) Troupe spam w/ DE/Eldar Back up
3) Pure Quin with dedicated rolls (some fusion units others with CC weapons)
Ive tried these 3 and honestly Troupe spam with Eldar back up IMO is the strongest, Ynnari IMO isnt that good for Quins.
I like the Fusion idea and i currently play with 6-7 fusion guns in my army, but i dont feel the fusion/ynnari spam is that good, yes it won a tournament once, but over all its actually very hit or miss.
IMO Eldar back up, a Farseer, Dark Reapers and Hornets with 4-5 Troupes with Troupe Masters/Shadowseer has done work for me. It can handle almost every situation.
These are just some thoughts from a person with 26-28 games with Harlequins.
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