Did you know Thresh can reveal stealth with his hook?
Did you know Quinn's Vault can stop dashes and Shen's ult? IE: If Leona tries to use Zenith Blade on your support, you can dash into her mid animation and cancel the attack. Same goes for Shen's ulti, her Vault cancels it.
A friendly Lulu does not synergize with J4's ultimate very well:
If J4 encloses an enemy in Cataclysm, the enemy can run to the edge of the wall. If Lulu then ults Jarvan, there is a chance the enemy will get knocked up and out of Cataclysm's confinements.
Ziggs's passive does 150% damage to structures. It also stacks with Lich Bane... which means Ziggs is probably one of the best objective-oriented mages in the game. Lich Bane + standard AP items = Inhibitor tower is dead in 4~ auto attacks in a standard-paced game.