Rat Plague

>Gameplan

We have a quite aggressive gameplan: We want to get as many rats as possible onto the battlefield to grow our Pack Rat and Rat Colony gigantic over the course of the game, until they (and the sheer mass of rats we have) can close the game out.

Disruption

As we first need to grow our rats before they are able to just eat every other creature on board, we have Inquisition of Kozilek, Thoughtseize s more cheaper brother, to keep bigger creatures away from the board and to keep our rats safe from Plague Engineer and other removal. It can't hit 4-mana-wraths, but Thoughtseize is too expensive and boardwipes aren't too much of a thing most of the time anyway.

The Swarm

Our game-ending rats are Rat Colony and Pack Rat, for a total of 14 threats. Pack Rat also can copy itself at the cost of discarding cards. For additional tribal payoff we have a full playset of Piper of the Swarm, being able to pump out more rats without having to spend cards and being able to steal the opponent's threats, possibly taking their win-condition away and ending the game by ourselves. This opens up the possibility of turning games around pretty fast. The most important thing about Piper of the Swarm is that it provides our rats evasion with menace. Having to chump-block with two creatures each time in the late game to prevent you from dying is not something the most decks can manage to do for a long time.

Fuel

As discarding cards for Pack Rat to create more big tokens is a thing that we want to do and to keep our hand filled with cards, we play Sign in Blood.

Spam the Board

To bring the rat count up quickly, we play literally every rat one drop available in Modern (except changelings). We don't really care about their abilities, the quantity is important. Typhoid Rats can be nice because of deathtouch hindering the opponent from attacking us with their threats.

Manabase

We play 22 lands, four of them being Castle Locthwain, enabling even more card-draw.

>Budget

This list has an okay budget, costing 30€ on cardmarket.