Rammus Build: "Vampiric Rammus"

My brother recently began playing League. While I was going over items with him in an ARAM match, my mind started to wander towards Rammus. I was playing Akali, and was going into Hextech Gunblade. He was Garen going into Spirit Visage. I was actually explaining Rammus to him when it clicked. So I threw together this build really quick and tested it in Blind Pick. It was a slow start, back and forth kills Top lane against Zed- but then late game the build really picked up and I started getting my kill streaks.

The basic idea of this concept- Hard Sustain. I figured, Rammus' damage redirection can be utilized to create sustain using 3 items:

Thornmail gives a nice Armor bonus and applies magic damage redirection based on Armor and Damage received. This, coupled with Rammus' W, gives Rammus his signature grind. Sorry Jinx. The focus of this concept relies on the damage being redirected back to attackers. Hextech Gunblade isn't a typical Rammus item. It provides Ability Power and Attack Damage which are beneficial. Its active is actually a great tool for a high-mobility tank. Our focus here, however, is the passive: Heals for 15% of damage dealt. This ends up returning health back to Rammus upon being attacked due to his damage redirection. All the stat bonuses from Spirit Visage are beneficial to any tank. Spirit Visage does lack any provision of Armor, however. Spirit Visage plays into this for its passive: increases all healing received by 25%.

So let's look at this: Level 9 Rammus (not going to happen for full build): Base Armor: 65.784 Thornmail Armor: 100 Lvl 5 W Armor- 120 Bonus Total: 220 Total: 285.784

Now let's say Rammus takes an even 100 damage from a single AA while his W is active:

Damage red. from Thornmail: 15 from damage, 55 from bonus Armor Damage red. from Defensive Ball Curl: 65 flat, 28.5784 from Armor Total: 163.5784 (more than he received lol)

Health received from Hextech Gunblade: 24.53676 Total Health received after Spirit Visage: 30.67095

Total Damage taken after health received: 69.32905

Note: The numbers would actually scale higher, considering Rammus will be higher than lvl 9 by the time the build is completed. These numbers also don't take into consideration Masteries.

I still have to tune the build. This is what I have for Masteries:

Ferocity- 18 Sorcery- 5 Double Edged Sword- 1 Vampirism- 5 Oppressor- 1 Piecing Thoughts- 5 Deathfire Touch- 1

Resolve- 12 Recovery- 5 Tough Skin- 1 Runic Armor- 5 Perseverance- 1