Cape Buffalo Wild Shape

Keen Smell. The buffalo has advantage on Wisdom (Perception) checks that rely on smell.

Charge. If the buffalo moves at least 20 feet straight toward a target and then hits it with a ram attack on the same turn, the target takes an extra 13 (3d8) bludgeoning damage. If the target is a creature, it must succeed on a DC 16 Strength saving throw or be knocked prone.

Survival Instinct. When angry, the buffalo gains +2 to melee damage rolls. You become angry when you hit an enemy with your ram attack and this lasts for the combat encounter, but then you have to rp as an angry cape buffalo.

Siege Monster. While in cape buffalo form and hit a building or a structure with a ram attack, any hit counts as a critical hit. Also, if you move back far enough to use your Charge ability, you roll 4x the normal dice, not just double.

Multiattack. You make a number of attacks equal to what you would have in your cape buffalo form, in addition to the following. If you have less than a half of your hp left, you can make an extra attack as part of the multiattack feature. 

Ram. Melee Weapon Attack: +8 to hit, reach 5 ft., one target. Hit: 19 (3d8 + 6) bludgeoning damage. If you ram someone into a wall, or charge them into a wall, you and your target make contested Strength Checks. If you win, they're stunned until the end of their next turn.

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