His R has an insane AOE slow. His clear is going to be phenomally better now with the W , E and passive change. He has more resists early game, again 100 % uptime from level 1, allowing him to clear way safer and also pull off some cool plays. 70 % bonus resists is nothing to laugh at. With tabis and deadmans he has 90 Armour, which is lets say 3 items level 12,

So (20 + 31.4 + 4.3(12) + 20 + 90) + (20 + 31.4 + 4.3(12) + 20 + 90)*.7 = Which would be 213 base, + 149 from his w, giving him 362 total armour with 100 % uptime. At level 12 with tabis, deadmans. Before he would he would have 213 + 120 = 323with 6/14 = 42 % uptime.

So pretty much at all points in the game he has more of a targeted stat with 100 % uptime, where you get far far more lategame of both vs having less early and having more of your off defensive state around midgame.

But, this is a moot point as alot of rammus's still maxed E, which is this case it would still provide far more stats than a level 1 W previously, with 100 % uptime. Idk how people were playing rammus before. But this allows for great zoning potential of their backline and a good distraction with good peels. Which is what he did previously. If you were playing dive the backline rammus solo you might have been doing it wrong. Along with the fact he can still dive the backline with another team member which is the situation where you would use it before.

This champion is going to be ridiculous and I feel people are overestimating how much he got buffed as a tank and losing movespeed on a tank like rammus isn't the worse as he's supposed to be a more supportive champ.