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TechniLink team for Shared power with scale shot+dual wingbeat dnite and surging strikes urshifu:
Shared Power TechniLink (pokepast.es)
WARNING:
If you ever, EVER, meet a team with stamina+battle/shell-armor/water immunity, ABORT IMMEDIATELY.
If just stamina, Urshifu's your only bet.
You could drop hp fire/diamond storm on diancie(you already have one on mag) and adopt protect on your move set to better utilize diancie as a lead. Protect against SR users that immediately pose a threat to diancie like ferro/lando/pert/heatran(if you don't have earth power) etc. You also have...