Just because you have a boring win con doesn't lower it's rarity. "You win the game" just isn't a text that you slap onto an uncommon as a side note. That win con having a boring requirement or leading to boring gameplay is completely separate issue.
Tap doesn't help that much with the win con being sorcery speed (though at least it ensures the creature needs haste or no longer have summoning sickness) since you can still activate the instant you meet the requirement. It's noteworthy that of the 25 cards that have the text "You win the game" 17 of those have tied that ability with the "at the beginning of your upkeep" trigger. That generally makes it sure the opponents have their turn to do something about you presenting a completed win-con on the board.
Anyway... I'm not really feeling the new suggestion. It essentially turns all your bears into Nekrataals or whatnot. Doesn't seem particularly green. That's way less powerful than the original card btw, which is kinda contradictory given you just moved it up in rarity. Something that I had in mind when talking about an "enormous bonus" was massive an Overrun effect. Big enough to end the game in most situations, but perhaps not in, say, multiplayer EDH.
Okay, now that it's rare, I feel I can play more with the trigger... maybe make it mythic...
was:
> When Runeclaw Elder enters the battlefield, draw a card. , Tap ten green 2/2 creatures without abilities with different names: You win the game.
becomes:
> Whenever a green 2/2 creature without abilities enters the battlefield, draw a card. Then, if you control ten or more green 2/2 creature's without abilities with different names, each of them deals damage equal to its power to any nonplayer target.
Well, the tokens Elemental, Bear, Boar, Lizard, Wolf, and Satyr were listed in the OP comment. It's notable that things like Grizzly Fate don't really work that well since the ability also has the "with different names" restriction. It admittedly seems quite easy to miss.
Uncommon? Alternative win con cards tend to be rare or mythic.
It also seems kinda boring. Personally I would be more interested in some enormous bonus that's essentially says "you win the game" but would be more fun. Preferably something that makes use of all those creatures.
I actually was going to make a much more complex card called (((Transfusion))) that did this plus some more and went to check my intuition on how this effect is cost - just to find the closest we got to this is a card with reinforce .
Could grant a keyword until end of turn, but could also just put the counters on your evasive creature. I prefer the non prebuilt option.
Obscure wording = red flag. Heck, the fact that the obscure wording changes the timing of the spell entirely from what you would expect may actually make it more complex than .
I do not see why you are so desperate to remove the X. I'd rather have it than a nonevergreen keyword ability. And I wouldn't even use kicker that way, because kicker is ideally supposed to be a kicker not the entirety of the effect.
If I want this at common, I can eat the red flag, but it's not bad as an effect, so maybe I don't want it at common anyway.
Lifecraft Awakening and Soul's Might cut kinda close (Untamed Might?), but strangely enough this isn't a thing yet. It could easily grant some keyword, such as trample, UEOT as well IMO.
A weird idea to get rid of the X so one could try to justify it at common (if the wording wasn't so obscure):
> Sorcery
> Pay any amount of mana, then put that many +1/+1 counters on target creature.
Multikicker xD:
> Sorcery
> Multikicker
> Put a +1/+1 counter on target creature for each time ~ was kicked.
Just because you have a boring win con doesn't lower it's rarity. "You win the game" just isn't a text that you slap onto an uncommon as a side note. That win con having a boring requirement or leading to boring gameplay is completely separate issue.
Tap doesn't help that much with the win con being sorcery speed (though at least it ensures the creature needs haste or no longer have summoning sickness) since you can still activate the instant you meet the requirement. It's noteworthy that of the 25 cards that have the text "You win the game" 17 of those have tied that ability with the "at the beginning of your upkeep" trigger. That generally makes it sure the opponents have their turn to do something about you presenting a completed win-con on the board.
Anyway... I'm not really feeling the new suggestion. It essentially turns all your bears into Nekrataals or whatnot. Doesn't seem particularly green. That's way less powerful than the original card btw, which is kinda contradictory given you just moved it up in rarity. Something that I had in mind when talking about an "enormous bonus" was massive an Overrun effect. Big enough to end the game in most situations, but perhaps not in, say, multiplayer EDH.
Okay, now that it's rare, I feel I can play more with the trigger... maybe make it mythic...
was:
> When Runeclaw Elder enters the battlefield, draw a card.
, Tap ten green 2/2 creatures without abilities with different names: You win the game.
becomes:
> Whenever a green 2/2 creature without abilities enters the battlefield, draw a card. Then, if you control ten or more green 2/2 creature's without abilities with different names, each of them deals damage equal to its power to any nonplayer target.
?
I liked the shorter text.
+
; rarity: uncommon >> rare
> "Uncommon? Alternative win con cards tend to be rare or mythic.
It also seems kinda boring."
Which is why it isn't rare or mythic. :)
Well, there's the Master of the Wild Hunt-option.
> "Also, sorcery speed 'win the game' is not good. Opoonents are supposed to get a turn to respond to alt win conditions."
Yeah, we can handle this... +
.
Well, the tokens Elemental, Bear, Boar, Lizard, Wolf, and Satyr were listed in the OP comment. It's notable that things like Grizzly Fate don't really work that well since the ability also has the "with different names" restriction. It admittedly seems quite easy to miss.
Gets a little more interesting once you realize you can see also: Grizzly Fate, Keeper of the Beasts, Curse of the Swine, Zendikar's Roil, Predatory Advantage, Monkey Cage, Fable of Wolf and Owl, Tolsimir Wolfsblood and others. That's because they provide green 2/2 creature tokens without abilities for Bears, Beasts, Boars, Elementals, Lizards, Monkeys, Wolves, and a white and green Legendary Wolf named Voja.
Also, sorcery speed 'win the game' is not good. Opoonents are supposed to get a turn to respond to alt win conditions.
Uncommon? Alternative win con cards tend to be rare or mythic.
It also seems kinda boring. Personally I would be more interested in some enormous bonus that's essentially says "you win the game" but would be more fun. Preferably something that makes use of all those creatures.
See Balduvian Bears, Barbary Apes, Bear Cub, Cylian Elf, Forest Bear, Grizzly Bears, Runeclaw Bear, Treetop Warden, Bear, Boar, Elemental, Lizard, Satyr, Voja, Wolf.
Reminder text not final. Primal comes with an overlay of an empty text box... maybe some flavor text. ;)
See Scathe Zombies.
I actually was going to make a much more complex card called (((Transfusion))) that did this plus some more and went to check my intuition on how this effect is cost - just to find the closest we got to this is a card with reinforce

.
Could grant a keyword until end of turn, but could also just put the counters on your evasive creature. I prefer the non prebuilt option.
Obscure wording = red flag. Heck, the fact that the obscure wording changes the timing of the spell entirely from what you would expect may actually make it more complex than
.
I do not see why you are so desperate to remove the X. I'd rather have it than a nonevergreen keyword ability. And I wouldn't even use kicker that way, because kicker is ideally supposed to be a kicker not the entirety of the effect.
If I want this at common, I can eat the red flag, but it's not bad as an effect, so maybe I don't want it at common anyway.
Lifecraft Awakening and Soul's Might cut kinda close (Untamed Might?), but strangely enough this isn't a thing yet. It could easily grant some keyword, such as trample, UEOT as well IMO.
A weird idea to get rid of the X so one could try to justify it at common (if the wording wasn't so obscure):
> Sorcery
> Pay any amount of mana, then put that many +1/+1 counters on target creature.
Multikicker xD:
> Sorcery

> Multikicker
> Put a +1/+1 counter on target creature for each time ~ was kicked.