Syr Konrad, the Grim Syr Konrad, the Grim is a powerhouse for graveyard-focused decks, punishing opponents whenever creatures die, are milled, or leave your graveyard
Most prominently, Momir Vig allows you to pay X mana to make a copy of a random creature that also costs X mana, spawning an entire alternative format called Momir Basic, where players build a deck using only mana sources and a Momir Vig avatar and battle with randomized creatures from all over Magic
You get pseudo-card advantage, which can allow you to cast spells that target your Vehicles, and it also gives out +1/+1 counters for each spell you cast during your turn
One issue with attack triggers is the vulnerability they require
There are of course minor variances in size due to printing mistakes, but, generally speaking, all traditional Magic cards will be the same size
Your sealed pool should have several cards that can help "fix" your mana, so try and play them if you can