Tom Whisker

should not be unique, also if u wanna make mill deck viable this mechanic should burn every methuselah's deck

When i was designing the card, I was strongly thinking about the main clans to have ani and obf together: nosferatu and nosferatu antitribe, even if other minions (enkidu...) have the same discipline at superior.

Usually these clans are not known for their big ousting power (except for nosferatu royalty g12) but more for their combat abilities (cock robin, beast, gunnelle, black annis...) or spying cards cards (shreknet, courrier, ...).
So the card originally i was thinking about was looking for two goals :
- making combat easier (random discard)
- depriving my prey from his bloat / combo arsenal by milling him.

I chose to make the retainer unique, to avoid combo killing decks : i don t think it would be funny for any player to see his library milled at once because it was bled by a minion with 10 tom whiskers... specially as some minion with ANI and OBF have a free unlock when recruiting retainers / animals ( cock robin, baba yaga, enkidu)

the enter combat part wording was linked to the fact that decks with ani have an almost innate ability to block with intercept as well as a few rusher (even if most except enkidu have basic animalism).

Maybe...

Tom whisker
unique animal retainer
no cost
1 life
Each time this retainer employer does an D action successfully, the target burns the 4 top cards from the library
As above, and when the minion employer is in combat, the opposing minion controller gets -1 hand size until end of combat.

why not something like this:

Tom whisker
unique animal retainer
no cost
1 life
Before combat name a card. The opposing minion cannot play that card in the first round of combat.
As above, and if opposing minion is still ready after combat he or she does not unlock in the next untap phase.

to nicktucku... try to imagine your version with enkidu... i dont think that it would be a good idea to allow him to prevent opposing minion to play majesty (for example but could be aid from bats and so on...)
Enkidu is in some ways capping the power of this card, unless we add in this case a requirement making enkidu unable to recruit it directly... but then would we need disciplines ?

and beside for superior version: i m not a big fan with "do no unlock next unlock phase" except when a card like mind numb allow it to be remembered :
let s say you make a bum s rush with baba yaga with tom whisker (superior) on lodin.
Lodin choses not to block, so he does not get locked => making superior power useless at first glance + needing to have a way to remind him to not unlock him next untap if he would go locked by then... (ok a deep song would have locked him but what if he plays second trad on another action later and get locked again for successfully blocking the action)...

+ why to stop making Tom whiskers a feline saboteur ? : D

I don't think this is broken, its unique needs 2 discipline and a recruit actionion. If u wanna restrict u can add a clan requirement like nosferatu and antitrubu or just an option for other players to steal/ destroy it as a D action.