10 Entreat The Angels Can Never Have Enough Casting Entreat the Angels normally is fine
Crew 4 (Tap any number of creatures you control with total power 4 or more: This Vehicle becomes an artifact creature until end of turn.) Mentor (Whenever this creature attacks, put a +1/+1 counter on target attacking creature with lesser power.) Whenever you attack with at least two creatures that have first strike, double strike, vigilance, and/or haste, transform Path of Mettle
That makes vintage cards, especially 1st Edition runs, exponentially scarcer by comparison
Once sold out, it will not be restocked
The problem with dedicating two cards in your deck this way is that you only have one card left with which to actually win the game
Better yet, you are able to choose two modes, which offers a lot of versatility for a single card