Each end step? Are you sure? Even ignoring this card's own token making, you could easily have 5-8 creatures by the time you drop this on turn 4-5, which is an insane life swing - gaining 10-16 life a round? That's way more than Clearwater Goblet could hope for, and fighting through a powered up Goblet was hard enough.

Even if it was only on your turn, the Conclave Phalanx effect every turn is going to be pretty tough to get through. I... guess it was recently seen on Elspeth Tirel as her +2, but she was a mythic planeswalker.

What you want to compare this card to is probably the Elfball decks from Onslaught. Pack 4x Wellwishers, and the Elfball player could sit around and gain piles of life every turn, until they had access to 21 mana, and would toss a 20 point Fireball at the opponent. Incredibly fragile, what with the entire deck falling apart to a single Tremor or Wrath of God. Of course, if your opponent wasn't playing with those cards, grind until you win.

Personally, though, I think this is more likely to play out like Clearwater Goblet, which, yeah, was an incredibly frustrating card to sit across the table from. But not exactly unreasonable... just really, really good. I suppose, in theory, Cavelord decks could regularly get 8+ creatures on the table... but at that point, they don't need a Cavelord. They need Overrun. I don't like to design too many stinkers that just waste everyone's time, but I got to admit that there are people that enjoy playing them, so they should get printed on rare occasions.

That said, if we're comparing this directly to Clearwater Goblet, though, then it is too cheap. The goblet has a rating of 4.269 and costs to use properly. Cavelord costs and can block. Normally, being a creature is a drawback... but in order to really exploit this mechanic, we're kind of assuming the opponent doesn't have access to a lot of creature kill anyway. I'd say the ability starts at 6cc, though I suspect it really costs 7. I'd probably adjust the p/t accordingly.