Modern-Age Tank Blastoise - Tundy

Guide

With the "bug fix" to the Spin + Spout build, Blastoise's true colors as a Defender are starting to shine. Surf is essentially a miniature version of Talonflame's ult, sweeping people off their tower while leaving them stunned the whole time. Hydro Pump is the icing on the stun cake, making sure your enemies don't get to play.
Go top and bully the other guys in lane. With your fancy glasses on, Water Gun does a respectable amount of damage and is a good last-hitting tool. Your Defenses and base HP are fantastic and you even have a good escape option in Skull Bash, so make cheeky plays to gain a lead on the enemy. Score Shield makes dunks of 10 or under almost unstoppable!
Hydro Pump is a better version of Water Gun, which is crazy since Water Gun was already doing fine. Make sure to spam your autos because your boosted auto reduces your cooldowns - also, getting hit with a slow and then Hydro Pump is extremely annoying. It also does damage three times (with the first hit boosted by Choice Specs), so it's great at stealing or securing camps.
Surf does basically everything you could ever want and then also more. Not only does it do stupid damage and gives you surprisingly good mobility for a tank, but it stuns people for up to 2 seconds and sweeps them way back. There's an argument for Rapid Spin to be made, but this move is just too bonkers to pass up from what I can tell.
Yet, still, this isn't even the best Blastoise has to offer. Once you become a fully evolved turtle you unlock one of if not the most cracked move in the game, Hydro Typhoon. Does insane damage and leaves people stunned for ~1.5-2s in a five kilometer radius. What's more? It recharges 10 seconds slower than Talon ult.

Overall, Blastoise excels at splitpushing and aiding the team with his fantastic defenses, abundant CC and good damage to show on top of it. He's a good lane bully and only becomes even worse to deal with as the game goes on. Happy blastin'!

OTHER ITEM OPTIONS:
Muscle Band -> Choice Specs: Better if you like burst damage from your spells
Choice Specs -> Energy Amplifier. Makes your jacked ult even more jacked. The enemy team will fear hearing the words "blastoise is ulting" over their comms. It's almost useless early to midgame though, so use at your own discretion.
Focus Band -> Buddy Barrier. Better in high-level competitive play and five stacks since you can fully abuse the big shield granted by Buddy.

Eject Button -> Goal-Getter. Not something I would seriously advise. However, if you're VERY confident in your positioning, this could be a good option to pair with your Score Shield abuse.